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http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#PARI.2FGP
PARI/GP
plothraw(vx, vy)
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Perl
Perl
use GD::Graph::points;   @data = ( [0, 1, 2, 3, 4, 5, 6, 7, 8, 9], [2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0], );   $graph = GD::Graph::points->new(400, 300); open my $fh, '>', "qsort-range-10-9.png"; binmode $fh; print $fh $graph->plot(\@data)->png; close $fh;
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#Objective-C
Objective-C
#import <Foundation/Foundation.h>   @interface RCPoint : NSObject { int x, y; } -(instancetype)initWithX:(int)x0; -(instancetype)initWithX:(int)x0 andY:(int)y0; -(instancetype)initWithPoint:(RCPoint *)p; @property (nonatomic) int x; @property (nonatomic) int y; @end   @implementation RCPoint @synthesize x, y; -(instancetype)initWithX:(int)x0 { return [self initWithX:x0 andY:0]; } -(instancetype)initWithX:(int)x0 andY:(int)y0 { if ((self = [super init])) { x = x0; y = y0; } return self; } -(instancetype)initWithPoint:(RCPoint *)p { return [self initWithX:p.x andY:p.y]; } -(NSString *)description { return [NSString stringWithFormat:@"<RCPoint %p x: %d y: %d>", self, x, y]; } @end   @interface RCCircle : RCPoint { int r; } -(instancetype)initWithCenter:(RCPoint *)p andRadius:(int)r0; -(instancetype)initWithX:(int)x0 andY:(int)y0 andRadius:(int)r0; -(instancetype)initWithCircle:(RCCircle *)c; @property (nonatomic) int r; @end   @implementation RCCircle @synthesize r; -(instancetype)initWithCenter:(RCPoint *)p andRadius:(int)r0 { if ((self = [super initWithPoint:p])) { r = r0; } return self; } -(instancetype)initWithX:(int)x0 andY:(int)y0 andRadius:(int)r0 { if ((self = [super initWithX:x0 andY:y0])) { r = r0; } return self; } -(instancetype)initWithCircle:(RCCircle *)c { return [self initWithX:c.x andY:c.y andRadius:c.r]; } -(NSString *)description { return [NSString stringWithFormat:@"<RCCircle %p x: %d y: %d r: %d>", self, x, y, r]; } @end   int main(int argc, const char *argv[]) { @autoreleasepool {   NSLog(@"%@", [[RCPoint alloc] init]); NSLog(@"%@", [[RCPoint alloc] initWithX:3]); NSLog(@"%@", [[RCPoint alloc] initWithX:3 andY:4]); NSLog(@"%@", [[RCCircle alloc] init]); NSLog(@"%@", [[RCCircle alloc] initWithX:3]); NSLog(@"%@", [[RCCircle alloc] initWithX:3 andY:4]); NSLog(@"%@", [[RCCircle alloc] initWithX:3 andY:4 andRadius:7]); RCPoint *p = [[RCPoint alloc] initWithX:1 andY:2]; NSLog(@"%@", [[RCCircle alloc] initWithPoint:p]); NSLog(@"%@", [[RCCircle alloc] initWithCenter:p andRadius:7]); NSLog(@"%d", p.x); // 1 p.x = 8; NSLog(@"%d", p.x); // 8   } return 0; }
http://rosettacode.org/wiki/Poker_hand_analyser
Poker hand analyser
Task Create a program to parse a single five card poker hand and rank it according to this list of poker hands. A poker hand is specified as a space separated list of five playing cards. Each input card has two characters indicating face and suit. Example 2d       (two of diamonds). Faces are:    a, 2, 3, 4, 5, 6, 7, 8, 9, 10, j, q, k Suits are:    h (hearts),   d (diamonds),   c (clubs),   and   s (spades),   or alternatively,   the unicode card-suit characters:    ♥ ♦ ♣ ♠ Duplicate cards are illegal. The program should analyze a single hand and produce one of the following outputs: straight-flush four-of-a-kind full-house flush straight three-of-a-kind two-pair one-pair high-card invalid Examples 2♥ 2♦ 2♣ k♣ q♦: three-of-a-kind 2♥ 5♥ 7♦ 8♣ 9♠: high-card a♥ 2♦ 3♣ 4♣ 5♦: straight 2♥ 3♥ 2♦ 3♣ 3♦: full-house 2♥ 7♥ 2♦ 3♣ 3♦: two-pair 2♥ 7♥ 7♦ 7♣ 7♠: four-of-a-kind 10♥ j♥ q♥ k♥ a♥: straight-flush 4♥ 4♠ k♠ 5♦ 10♠: one-pair q♣ 10♣ 7♣ 6♣ q♣: invalid The programs output for the above examples should be displayed here on this page. Extra credit use the playing card characters introduced with Unicode 6.0 (U+1F0A1 - U+1F0DE). allow two jokers use the symbol   joker duplicates would be allowed (for jokers only) five-of-a-kind would then be the highest hand More extra credit examples joker 2♦ 2♠ k♠ q♦: three-of-a-kind joker 5♥ 7♦ 8♠ 9♦: straight joker 2♦ 3♠ 4♠ 5♠: straight joker 3♥ 2♦ 3♠ 3♦: four-of-a-kind joker 7♥ 2♦ 3♠ 3♦: three-of-a-kind joker 7♥ 7♦ 7♠ 7♣: five-of-a-kind joker j♥ q♥ k♥ A♥: straight-flush joker 4♣ k♣ 5♦ 10♠: one-pair joker k♣ 7♣ 6♣ 4♣: flush joker 2♦ joker 4♠ 5♠: straight joker Q♦ joker A♠ 10♠: straight joker Q♦ joker A♦ 10♦: straight-flush joker 2♦ 2♠ joker q♦: four-of-a-kind Related tasks Playing cards Card shuffles Deal cards_for_FreeCell War Card_Game Go Fish
#Seed7
Seed7
$ include "seed7_05.s7i"; include "console.s7i";   const string: face is "A23456789TJQK"; const string: suit is "♥♦♣♠";   const func string: analyzeHand (in array integer: faceCnt, in array integer: suitCnt) is func result var string: handValue is ""; local var boolean: pair1 is FALSE; var boolean: pair2 is FALSE; var boolean: three is FALSE; var boolean: four is FALSE; var boolean: flush is FALSE; var boolean: straight is FALSE; var integer: sequence is 0; var integer: x is 0; begin for x range 1 to 13 do case faceCnt[x] of when {2}: if pair1 then pair2 := TRUE; else pair1 := TRUE; end if; when {3}: three := TRUE; when {4}: four := TRUE; end case; end for; for x range 1 to 4 until flush do if suitCnt[x] = 5 then flush := TRUE; end if; end for; if not pair1 and not three and not four then for x range 1 to 13 until sequence = 5 do if faceCnt[x] <> 0 then incr(sequence); else sequence := 0; end if; end for; straight := sequence = 5 or (sequence = 4 and faceCnt[1] <> 0); end if; if straight and flush then handValue := "straight-flush"; elsif four then handValue := "four-of-a-kind"; elsif pair1 and three then handValue := "full-house"; elsif flush then handValue := "flush"; elsif straight then handValue := "straight"; elsif three then handValue := "three-of-a-kind"; elsif pair1 and pair2 then handValue := "two-pair"; elsif pair1 then handValue := "one-pair"; else handValue := "high-card"; end if; end func;   const proc: analyze (in string: cards) is func local var array integer: faceCnt is 13 times 0; var array integer: suitCnt is 4 times 0; var string: card is ""; begin for card range split(upper(cards), ' ') do incr(faceCnt[pos(face, card[1])]); incr(suitCnt[pos(suit, card[2])]); end for; writeln(cards <& ": " <& analyzeHand(faceCnt, suitCnt)); end func;   const proc: main is func begin OUT := STD_CONSOLE; analyze("2♥ 2♦ 2♠ k♠ q♦"); analyze("2♥ 5♥ 7♦ 8♠ 9♦"); analyze("a♥ 2♦ 3♠ 4♠ 5♠"); analyze("2♥ 3♥ 2♦ 3♠ 3♦"); analyze("2♥ 7♥ 2♦ 3♠ 3♦"); analyze("2♥ 7♥ 7♦ 7♠ 7♣"); analyze("t♥ j♥ q♥ k♥ a♥"); analyze("4♥ 4♣ k♣ 5♦ t♣"); analyze("q♣ t♣ 7♣ 6♣ 4♣"); end func;
http://rosettacode.org/wiki/Population_count
Population count
Population count You are encouraged to solve this task according to the task description, using any language you may know. The   population count   is the number of   1s   (ones)   in the binary representation of a non-negative integer. Population count   is also known as:   pop count   popcount   sideways sum   bit summation   Hamming weight For example,   5   (which is   101   in binary)   has a population count of   2. Evil numbers   are non-negative integers that have an   even   population count. Odious numbers     are  positive integers that have an    odd   population count. Task write a function (or routine) to return the population count of a non-negative integer. all computation of the lists below should start with   0   (zero indexed). display the   pop count   of the   1st   thirty powers of   3       (30,   31,   32,   33,   34,   ∙∙∙   329). display the   1st   thirty     evil     numbers. display the   1st   thirty   odious   numbers. display each list of integers on one line   (which may or may not include a title),   each set of integers being shown should be properly identified. See also The On-Line Encyclopedia of Integer Sequences:   A000120 population count. The On-Line Encyclopedia of Integer Sequences:   A000069 odious numbers. The On-Line Encyclopedia of Integer Sequences:   A001969 evil numbers.
#Go
Go
package main   import ( "fmt" "math/bits" )   func main() { fmt.Println("Pop counts, powers of 3:") n := uint64(1) // 3^0 for i := 0; i < 30; i++ { fmt.Printf("%d ", bits.OnesCount64(n)) n *= 3 } fmt.Println() fmt.Println("Evil numbers:") var od [30]uint64 var ne, no int for n = 0; ne+no < 60; n++ { if bits.OnesCount64(n)&1 == 0 { if ne < 30 { fmt.Printf("%d ", n) ne++ } } else { if no < 30 { od[no] = n no++ } } } fmt.Println() fmt.Println("Odious numbers:") for _, n := range od { fmt.Printf("%d ", n) } fmt.Println() }
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#Sidef
Sidef
func poly_long_div(rn, rd) {   var n = rn.map{_} var gd = rd.len   if (n.len >= gd) { return(gather { while (n.len >= gd) { var piv = n[0]/rd[0] take(piv) { |i| n[i] -= (rd[i] * piv) } << ^(n.len `min` gd) n.shift } }, n) }   return([0], rn) }
http://rosettacode.org/wiki/Polynomial_regression
Polynomial regression
Find an approximating polynomial of known degree for a given data. Example: For input data: x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}; The approximating polynomial is: 3 x2 + 2 x + 1 Here, the polynomial's coefficients are (3, 2, 1). This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#R
R
  x <- c(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) y <- c(1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321) coef(lm(y ~ x + I(x^2)))
http://rosettacode.org/wiki/Power_set
Power set
A   set   is a collection (container) of certain values, without any particular order, and no repeated values. It corresponds with a finite set in mathematics. A set can be implemented as an associative array (partial mapping) in which the value of each key-value pair is ignored. Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S. Task By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S. For example, the power set of     {1,2,3,4}     is {{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}. For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set. The power set of the empty set is the set which contains itself (20 = 1): P {\displaystyle {\mathcal {P}}} ( ∅ {\displaystyle \varnothing } ) = { ∅ {\displaystyle \varnothing } } And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2): P {\displaystyle {\mathcal {P}}} ({ ∅ {\displaystyle \varnothing } }) = { ∅ {\displaystyle \varnothing } , { ∅ {\displaystyle \varnothing } } } Extra credit: Demonstrate that your language supports these last two powersets.
#jq
jq
def powerset: reduce .[] as $i ([[]]; reduce .[] as $r (.; . + [$r + [$i]]));
http://rosettacode.org/wiki/Primality_by_trial_division
Primality by trial division
Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops are allowed. Related tasks   count in factors   prime decomposition   AKS test for primes   factors of an integer   Sieve of Eratosthenes   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Emacs_Lisp
Emacs Lisp
(defun prime (a) (not (or (< a 2) (cl-loop for x from 2 to (sqrt a) when (zerop (% a x)) return t))))
http://rosettacode.org/wiki/Price_fraction
Price fraction
A friend of mine runs a pharmacy.   He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value.   This value is regulated by a government department. Task Given a floating point value between   0.00   and   1.00,   rescale according to the following table: >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00
#Nim
Nim
import random, strformat   # Representation of a standard value as an int (actual value * 100). type StandardValue = distinct int   proc `<`(a, b: StandardValue): bool {.borrow.}   const Pricemap = [10, 18, 26, 32, 38, 44, 50, 54, 58, 62, 66, 70, 74, 78, 82, 86, 90, 94, 98, 100]     proc toStandardValue(f: float): StandardValue = ## Convert a float to a standard value (decimal value multiplied by 100). ## Index: 0.01..0.05 -> 0, 0.06..0.10 -> 1, 0.11..0.15 -> 2... var value = int(f * 100) if value == 0: return StandardValue(10) dec value # Increment index every 5 of value, so value in 1..100 translates to index in 0..19. let index = 2 * (value div 10) + (value mod 10) div 5 result = StandardValue(Pricemap[index])     proc `$`(price: StandardValue): string = ## Return the string representation of a standard value. if price < StandardValue(10): "0.0" & $int(price) elif price < StandardValue(100): "0." & $int(price) else: "1.00"     when isMainModule: randomize() for _ in 0 .. 10: let price = rand(1.01) echo &"Price for {price:.2f} is {price.toStandardValue()}"
http://rosettacode.org/wiki/Price_fraction
Price fraction
A friend of mine runs a pharmacy.   He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value.   This value is regulated by a government department. Task Given a floating point value between   0.00   and   1.00,   rescale according to the following table: >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00
#Objeck
Objeck
class PriceFraction { function : Main(args : String[]) ~ Nil { for(i := 0; i < 5; i++;) { f := Float->Random(); r := SpecialRound(f); "{$f} -> {$r}"->PrintLine(); }; }   function : SpecialRound(inValue : Float) ~ Float { if (inValue > 1) { return 1; };   splitters := [ 0.00 , 0.06 , 0.11 , 0.16 , 0.21 , 0.26 , 0.31 , 0.36 , 0.41 , 0.46 , 0.51 , 0.56 , 0.61 , 0.66 , 0.71 , 0.76 , 0.81 , 0.86 , 0.91 , 0.96 ];   replacements := [ 0.10 , 0.18 , 0.26 , 0.32 , 0.38 , 0.44 , 0.50 , 0.54 , 0.58 , 0.62 , 0.66 , 0.70 , 0.74 , 0.78 , 0.82 , 0.86 , 0.90 , 0.94 , 0.98 , 1.00 ];   for(x := 0; x < splitters->Size() - 1; x+=1;) { if (inValue >= splitters[x] & inValue < splitters[x + 1]) { return replacements[x]; }; };   return inValue; } }
http://rosettacode.org/wiki/Proper_divisors
Proper divisors
The   proper divisors   of a positive integer N are those numbers, other than N itself, that divide N without remainder. For N > 1 they will always include 1,   but for N == 1 there are no proper divisors. Examples The proper divisors of     6     are   1, 2, and 3. The proper divisors of   100   are   1, 2, 4, 5, 10, 20, 25, and 50. Task Create a routine to generate all the proper divisors of a number. use it to show the proper divisors of the numbers 1 to 10 inclusive. Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has. Show all output here. Related tasks   Amicable pairs   Abundant, deficient and perfect number classifications   Aliquot sequence classifications   Factors of an integer   Prime decomposition
#PowerShell
PowerShell
  function proper-divisor ($n) { if($n -ge 2) { $lim = [Math]::Floor([Math]::Sqrt($n)) $less, $greater = @(1), @() for($i = 2; $i -lt $lim; $i++){ if($n%$i -eq 0) { $less += @($i) $greater = @($n/$i) + $greater } } if(($lim -ne 1) -and ($n%$lim -eq 0)) {$less += @($lim)} $($less + $greater) } else {@()} } "$(proper-divisor 100)" "$(proper-divisor 496)" "$(proper-divisor 2048)"  
http://rosettacode.org/wiki/Priority_queue
Priority queue
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order. Task Create a priority queue.   The queue must support at least two operations:   Insertion.   An element is added to the queue with a priority (a numeric value).   Top item removal.   Deletes the element or one of the elements with the current top priority and return it. Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc. To test your implementation, insert a number of elements into the queue, each with some random priority. Then dequeue them sequentially; now the elements should be sorted by priority. You can use the following task/priority items as input data: Priority Task ══════════ ════════════════ 3 Clear drains 4 Feed cat 5 Make tea 1 Solve RC tasks 2 Tax return The implementation should try to be efficient.   A typical implementation has   O(log n)   insertion and extraction time,   where   n   is the number of items in the queue. You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc.   If so, discuss the reasons behind it.
#Raku
Raku
class PriorityQueue { has @!tasks;   method insert (Int $priority where * >= 0, $task) { @!tasks[$priority].push: $task; }   method get { @!tasks.first(?*).shift }   method is-empty { ?none @!tasks } }   my $pq = PriorityQueue.new;   for ( 3, 'Clear drains', 4, 'Feed cat', 5, 'Make tea', 9, 'Sleep', 3, 'Check email', 1, 'Solve RC tasks', 9, 'Exercise', 2, 'Do taxes' ) -> $priority, $task { $pq.insert( $priority, $task ); }   say $pq.get until $pq.is-empty;
http://rosettacode.org/wiki/Prime_decomposition
Prime decomposition
The prime decomposition of a number is defined as a list of prime numbers which when all multiplied together, are equal to that number. Example 12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3} Task Write a function which returns an array or collection which contains the prime decomposition of a given number   n {\displaystyle n}   greater than   1. If your language does not have an isPrime-like function available, you may assume that you have a function which determines whether a number is prime (note its name before your code). If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes. Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc). Related tasks   count in factors   factors of an integer   Sieve of Eratosthenes   primality by trial division   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Julia
Julia
  julia> Pkg.add("Primes") julia> factor(8796093022207) [9719=>1,431=>1,2099863=>1]  
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Processing
Processing
  //Aamrun, 26th June 2022   int x[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; float y[] = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0};   size(300,300); surface.setTitle("Rosetta Plot");   stroke(#ff0000);   for(int i=0;i<x.length;i++){ ellipse(x[i],y[i],3,3); }    
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#OCaml
OCaml
class point ?(x=0.0) ?(y=0.0) () = (* extra () used to erase the optional parameters *) object (self) val mutable x = x val mutable y = y   method x = x method y = y method set_x x' = x <- x' method set_y y' = y <- y' method print = Printf.sprintf "Point (%f, %f)" x y method copy = {< >} end   class circle ?(r=1.0) ?(x=0.0) ?(y=0.0) () = object (self) inherit point ~x:x ~y:y () val mutable r = r   method r = r method set_r r' = r <- r' method print = Printf.sprintf "Circle (%f, %f, %f)" r x y end   let print x = print_endline x#print   let () = let p = new point () in let c = new circle () in print c; print p; c#set_x 10.0; print c; print (new point ~y:2.1 ())
http://rosettacode.org/wiki/Poker_hand_analyser
Poker hand analyser
Task Create a program to parse a single five card poker hand and rank it according to this list of poker hands. A poker hand is specified as a space separated list of five playing cards. Each input card has two characters indicating face and suit. Example 2d       (two of diamonds). Faces are:    a, 2, 3, 4, 5, 6, 7, 8, 9, 10, j, q, k Suits are:    h (hearts),   d (diamonds),   c (clubs),   and   s (spades),   or alternatively,   the unicode card-suit characters:    ♥ ♦ ♣ ♠ Duplicate cards are illegal. The program should analyze a single hand and produce one of the following outputs: straight-flush four-of-a-kind full-house flush straight three-of-a-kind two-pair one-pair high-card invalid Examples 2♥ 2♦ 2♣ k♣ q♦: three-of-a-kind 2♥ 5♥ 7♦ 8♣ 9♠: high-card a♥ 2♦ 3♣ 4♣ 5♦: straight 2♥ 3♥ 2♦ 3♣ 3♦: full-house 2♥ 7♥ 2♦ 3♣ 3♦: two-pair 2♥ 7♥ 7♦ 7♣ 7♠: four-of-a-kind 10♥ j♥ q♥ k♥ a♥: straight-flush 4♥ 4♠ k♠ 5♦ 10♠: one-pair q♣ 10♣ 7♣ 6♣ q♣: invalid The programs output for the above examples should be displayed here on this page. Extra credit use the playing card characters introduced with Unicode 6.0 (U+1F0A1 - U+1F0DE). allow two jokers use the symbol   joker duplicates would be allowed (for jokers only) five-of-a-kind would then be the highest hand More extra credit examples joker 2♦ 2♠ k♠ q♦: three-of-a-kind joker 5♥ 7♦ 8♠ 9♦: straight joker 2♦ 3♠ 4♠ 5♠: straight joker 3♥ 2♦ 3♠ 3♦: four-of-a-kind joker 7♥ 2♦ 3♠ 3♦: three-of-a-kind joker 7♥ 7♦ 7♠ 7♣: five-of-a-kind joker j♥ q♥ k♥ A♥: straight-flush joker 4♣ k♣ 5♦ 10♠: one-pair joker k♣ 7♣ 6♣ 4♣: flush joker 2♦ joker 4♠ 5♠: straight joker Q♦ joker A♠ 10♠: straight joker Q♦ joker A♦ 10♦: straight-flush joker 2♦ 2♠ joker q♦: four-of-a-kind Related tasks Playing cards Card shuffles Deal cards_for_FreeCell War Card_Game Go Fish
#Standard_ML
Standard ML
  local val rec ins = fn x : int*'a => fn [] => [x] | ll as h::t => if #1 x<= (#1 h) then x::ll else h::ins x t val rec acount = fn (n,a::(b::t)) => if a=b then acount (n+1,b::t) else (n,a)::acount(1,b::t) | (n,[t]) => [(n,t)] in (* helper count and sort functions *) val rec sortBy1st = fn [] => [] | h::t => ins h (sortBy1st t) val addcount = fn ll => acount (1,ll) end;       val showHand = fn input => let exception Cheat of string (* replace a j q k by their numbers *) val translateCardstrings = fn inputstr => String.tokens (fn #" "=>true|_=>false) (String.translate (fn #"a"=>"1"| #"j"=>"11"| #"q"=>"12"| #"k"=>"13" | a=>str a ) inputstr )   (* parse numbers and characters into int*strings and order those *) val parseFacesSuits = fn cardcodes => sortBy1st (List.map (fn el => (valOf (Int.fromString el ),String.extract (el,String.size el -1,NONE) )) cardcodes ) handle Option => raise Cheat "parse"   (* replace the list of face numbers by a list of every face with its count and order it / descending count *) val countAndSort =fn li => let val hand = ListPair.unzip li in (rev (sortBy1st (addcount (#1 hand))) , #2 hand ) end;     val score = fn ( (4,_)::t , _ ) => "four-of-a-kind" | ( (3,_)::(2,_)::t , _ ) => "full-house" | ( (3,_)::t,_) => "three-of-a-kind" | ( (2,_)::(2,_)::t,_) => "two-pair" | ( (2,_)::t,_) => "one-pair" | (x as (1,_)::t,ll) => if #2 (hd x ) - (#2 (hd (rev x))) =4 orelse ( #2 (hd (rev x)) = 1 andalso #2 (hd (tl (rev x))) =10 ) then if List.all (fn x => hd ll=x) ll then "straight-flush" else "straight" else if List.all (fn x => hd ll=x) ll then "flush" else "high-card" | _ => "invalid"       (* return 'invalid' if any duplicates or invalid codes *) val validate = fn lpair : (int * string) list => let val rec uniq = fn ([],y) =>true|(x,y) => List.filter (fn a=>a= hd x) y = [hd x] andalso uniq(tl x,y) in if List.all (fn x :int*string => #1 x > 0 andalso #1 x < 14 ) lpair andalso List.all (fn (x) => Option.isSome ( List.find (fn a=> a= #2x) ["c","d","h","s"] ) ) lpair andalso uniq (lpair ,lpair) then lpair else raise Cheat "value" end   in     ( score o countAndSort o validate o parseFacesSuits o translateCardstrings ) input handle Cheat ch => "invalid"   end;  
http://rosettacode.org/wiki/Population_count
Population count
Population count You are encouraged to solve this task according to the task description, using any language you may know. The   population count   is the number of   1s   (ones)   in the binary representation of a non-negative integer. Population count   is also known as:   pop count   popcount   sideways sum   bit summation   Hamming weight For example,   5   (which is   101   in binary)   has a population count of   2. Evil numbers   are non-negative integers that have an   even   population count. Odious numbers     are  positive integers that have an    odd   population count. Task write a function (or routine) to return the population count of a non-negative integer. all computation of the lists below should start with   0   (zero indexed). display the   pop count   of the   1st   thirty powers of   3       (30,   31,   32,   33,   34,   ∙∙∙   329). display the   1st   thirty     evil     numbers. display the   1st   thirty   odious   numbers. display each list of integers on one line   (which may or may not include a title),   each set of integers being shown should be properly identified. See also The On-Line Encyclopedia of Integer Sequences:   A000120 population count. The On-Line Encyclopedia of Integer Sequences:   A000069 odious numbers. The On-Line Encyclopedia of Integer Sequences:   A001969 evil numbers.
#Haskell
Haskell
import Data.Bits (popCount)   printPops :: (Show a, Integral a) => String -> [a] -> IO () printPops title counts = putStrLn $ title ++ show (take 30 counts)   main :: IO () main = do printPops "popcount " $ map popCount $ iterate (*3) (1 :: Integer) printPops "evil " $ filter (even . popCount) ([0..] :: [Integer]) printPops "odious " $ filter ( odd . popCount) ([0..] :: [Integer])
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#Slate
Slate
define: #Polynomial &parents: {Comparable} &slots: {#coefficients -> ExtensibleArray new}.   p@(Polynomial traits) new &capacity: n [ p cloneSettingSlots: #(coefficients) to: {p coefficients new &capacity: n} ].   p@(Polynomial traits) newFrom: seq@(Sequence traits) [ p clone `>> [coefficients: (seq as: p coefficients). normalize. ] ].   p@(Polynomial traits) copy [ p cloneSettingSlots: #(coefficients) to: {p coefficients copy} ].   p1@(Polynomial traits) >= p2@(Polynomial traits) [p1 degree >= p2 degree].   p@(Polynomial traits) degree [p coefficients indexOfLastSatisfying: [| :n | n isZero not]].   p@(Polynomial traits) normalize [ [p degree isPositive /\ [p coefficients last isZero]] whileTrue: [p coefficients removeLast] ].   p@(Polynomial traits) * n@(Number traits) [ p newFrom: (p coefficients collect: [| :x | x * n]) ].   p@(Polynomial traits) / n@(Number traits) [ p newFrom: (p coefficients collect: [| :x | x / n]) ].   p1@(Polynomial traits) minusCoefficients: p2@(Polynomial traits) [ p1 newFrom: (p1 coefficients with: p2 coefficients collect: #- `er) ].   p@(Polynomial traits) / denom@(Polynomial traits) [ p >= denom ifTrue: [| n q | n: p copy. q: p new. [n >= denom] whileTrue: [| piv | piv: p coefficients last / denom coefficients last. q coefficients add: piv. n: (n minusCoefficients: denom * piv). n normalize]. n coefficients isEmpty ifTrue: [n coefficients add: 0]. {q. n}] ifFalse: [{p newFrom: #(0). p copy}] ].
http://rosettacode.org/wiki/Polynomial_regression
Polynomial regression
Find an approximating polynomial of known degree for a given data. Example: For input data: x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}; The approximating polynomial is: 3 x2 + 2 x + 1 Here, the polynomial's coefficients are (3, 2, 1). This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Racket
Racket
  #lang racket (require math plot)   (define xs '(0 1 2 3 4 5 6 7 8 9 10)) (define ys '(1 6 17 34 57 86 121 162 209 262 321))   (define (fit x y n) (define Y (->col-matrix y)) (define V (vandermonde-matrix x (+ n 1))) (define VT (matrix-transpose V)) (matrix->vector (matrix-solve (matrix* VT V) (matrix* VT Y))))   (define ((poly v) x) (for/sum ([c v] [i (in-naturals)]) (* c (expt x i))))   (plot (list (points (map vector xs ys)) (function (poly (fit xs ys 2)))))  
http://rosettacode.org/wiki/Power_set
Power set
A   set   is a collection (container) of certain values, without any particular order, and no repeated values. It corresponds with a finite set in mathematics. A set can be implemented as an associative array (partial mapping) in which the value of each key-value pair is ignored. Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S. Task By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S. For example, the power set of     {1,2,3,4}     is {{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}. For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set. The power set of the empty set is the set which contains itself (20 = 1): P {\displaystyle {\mathcal {P}}} ( ∅ {\displaystyle \varnothing } ) = { ∅ {\displaystyle \varnothing } } And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2): P {\displaystyle {\mathcal {P}}} ({ ∅ {\displaystyle \varnothing } }) = { ∅ {\displaystyle \varnothing } , { ∅ {\displaystyle \varnothing } } } Extra credit: Demonstrate that your language supports these last two powersets.
#Julia
Julia
  function powerset{T}(x::Vector{T}) result = Vector{T}[[]] for elem in x, j in eachindex(result) push!(result, [result[j] ; elem]) end result end  
http://rosettacode.org/wiki/Primality_by_trial_division
Primality by trial division
Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops are allowed. Related tasks   count in factors   prime decomposition   AKS test for primes   factors of an integer   Sieve of Eratosthenes   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Erlang
Erlang
is_prime(N) when N == 2 -> true; is_prime(N) when N < 2 orelse N rem 2 == 0 -> false; is_prime(N) -> is_prime(N,3).   is_prime(N,K) when K*K > N -> true; is_prime(N,K) when N rem K == 0 -> false; is_prime(N,K) -> is_prime(N,K+2).
http://rosettacode.org/wiki/Price_fraction
Price fraction
A friend of mine runs a pharmacy.   He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value.   This value is regulated by a government department. Task Given a floating point value between   0.00   and   1.00,   rescale according to the following table: >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00
#OCaml
OCaml
let price_fraction v = if v < 0.0 || v >= 1.01 then invalid_arg "price_fraction"; let rec aux = function | (x,r)::tl -> if v < x then r else aux tl | [] -> assert false in aux [ 0.06, 0.10; 0.11, 0.18; 0.16, 0.26; 0.21, 0.32; 0.26, 0.38; 0.31, 0.44; 0.36, 0.50; 0.41, 0.54; 0.46, 0.58; 0.51, 0.62; 0.56, 0.66; 0.61, 0.70; 0.66, 0.74; 0.71, 0.78; 0.76, 0.82; 0.81, 0.86; 0.86, 0.90; 0.91, 0.94; 0.96, 0.98; 1.01, 1.00; ]
http://rosettacode.org/wiki/Proper_divisors
Proper divisors
The   proper divisors   of a positive integer N are those numbers, other than N itself, that divide N without remainder. For N > 1 they will always include 1,   but for N == 1 there are no proper divisors. Examples The proper divisors of     6     are   1, 2, and 3. The proper divisors of   100   are   1, 2, 4, 5, 10, 20, 25, and 50. Task Create a routine to generate all the proper divisors of a number. use it to show the proper divisors of the numbers 1 to 10 inclusive. Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has. Show all output here. Related tasks   Amicable pairs   Abundant, deficient and perfect number classifications   Aliquot sequence classifications   Factors of an integer   Prime decomposition
#Prolog
Prolog
divisor(N, Divisor) :- UpperBound is round(sqrt(N)), between(1, UpperBound, D), 0 is N mod D, ( Divisor = D ; LargerDivisor is N/D, LargerDivisor =\= D, Divisor = LargerDivisor ).   proper_divisor(N, D) :- divisor(N, D), D =\= N.     %% Task 1 %   proper_divisors(N, Ds) :- setof(D, proper_divisor(N, D), Ds).     %% Task 2 %   show_proper_divisors_of_range(Low, High) :- findall( N:Ds, ( between(Low, High, N), proper_divisors(N, Ds) ), Results ), maplist(writeln, Results).     %% Task 3 %   proper_divisor_count(N, Count) :- proper_divisors(N, Ds), length(Ds, Count).   find_most_proper_divisors_in_range(Low, High, Result) :- aggregate_all( max(Count, N), ( between(Low, High, N), proper_divisor_count(N, Count) ), max(MaxCount, Num) ), Result = (num(Num)-divisor_count(MaxCount)).
http://rosettacode.org/wiki/Priority_queue
Priority queue
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order. Task Create a priority queue.   The queue must support at least two operations:   Insertion.   An element is added to the queue with a priority (a numeric value).   Top item removal.   Deletes the element or one of the elements with the current top priority and return it. Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc. To test your implementation, insert a number of elements into the queue, each with some random priority. Then dequeue them sequentially; now the elements should be sorted by priority. You can use the following task/priority items as input data: Priority Task ══════════ ════════════════ 3 Clear drains 4 Feed cat 5 Make tea 1 Solve RC tasks 2 Tax return The implementation should try to be efficient.   A typical implementation has   O(log n)   insertion and extraction time,   where   n   is the number of items in the queue. You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc.   If so, discuss the reasons behind it.
#REXX
REXX
/*REXX program implements a priority queue with insert/display/delete the top task.*/ #=0; @.= /*0 tasks; nullify the priority queue.*/ say '══════ inserting tasks.'; call .ins 3 "Clear drains" call .ins 4 "Feed cat" call .ins 5 "Make tea" call .ins 1 "Solve RC tasks" call .ins 2 "Tax return" call .ins 6 "Relax" call .ins 6 "Enjoy" say '══════ showing tasks.'; call .show say '══════ deletes top task.'; say .del() /*delete the top task. */ exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ .del: procedure expose @. #; arg p; if p='' then p=.top(); y=@.p; @.p=; return y .ins: procedure expose @. #; #=#+1; @.#=arg(1); return # /*entry, P, task.*/ .show: procedure expose @. #; do j=1 for #; _=@.j; if _\=='' then say _; end; return /*──────────────────────────────────────────────────────────────────────────────────────*/ .top: procedure expose @. #; top=; top#= do j=1 for #; _=word(@.j, 1); if _=='' then iterate if top=='' | _>top then do; top=_; top#=j; end end /*j*/ return top#
http://rosettacode.org/wiki/Prime_decomposition
Prime decomposition
The prime decomposition of a number is defined as a list of prime numbers which when all multiplied together, are equal to that number. Example 12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3} Task Write a function which returns an array or collection which contains the prime decomposition of a given number   n {\displaystyle n}   greater than   1. If your language does not have an isPrime-like function available, you may assume that you have a function which determines whether a number is prime (note its name before your code). If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes. Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc). Related tasks   count in factors   factors of an integer   Sieve of Eratosthenes   primality by trial division   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Kotlin
Kotlin
// version 1.0.6   import java.math.BigInteger   val bigTwo = BigInteger.valueOf(2L) val bigThree = BigInteger.valueOf(3L)   fun getPrimeFactors(n: BigInteger): MutableList<BigInteger> { val factors = mutableListOf<BigInteger>() if (n < bigTwo) return factors if (n.isProbablePrime(20)) { factors.add(n) return factors } var factor = bigTwo var nn = n while (true) { if (nn % factor == BigInteger.ZERO) { factors.add(factor) nn /= factor if (nn == BigInteger.ONE) return factors if (nn.isProbablePrime(20)) factor = nn } else if (factor >= bigThree) factor += bigTwo else factor = bigThree } }   fun main(args: Array<String>) { val primes = intArrayOf(2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97) for (prime in primes) { val bigPow2 = bigTwo.pow(prime) - BigInteger.ONE println("2^${"%2d".format(prime)} - 1 = ${bigPow2.toString().padEnd(30)} => ${getPrimeFactors(bigPow2)}") } }
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Phix
Phix
-- -- demo\rosetta\Plot_coordinate_pairs.exw -- ====================================== -- with javascript_semantics include pGUI.e include IupGraph.e constant x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}, y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0} function get_data(Ihandle graph) return {{x,y,CD_BLUE}} end function IupOpen() Ihandle graph = IupGraph(get_data), dlg = IupDialog(graph,`TITLE="Plot coordinate pairs"`) IupSetAttributes(dlg,"RASTERSIZE=320x240,MINSIZE=320x200") IupSetAttributes(graph,"XTICK=1,XMIN=0,XMAX=9") IupSetAttributes(graph,"YTICK=20,YMIN=0,YMAX=180") IupShow(dlg) if platform()!=JS then IupMainLoop() IupClose() end if
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#Oforth
Oforth
Object Class new: Point(x, y) Point method: initialize(x, y) x := x y := y ; Point method: _x @x ; Point method: _y @y ; Point method: << "(" << @x << ", " << @y << ")" << ;   Object Class new: Circle(x, y, r) Circle method: initialize(x, y, r) x := x y := y r := r ; Circle method: _x @x ; Circle method: _y @y ; Circle method: _r @r ; Circle method: << "(" << @x << ", " << @y << ", " << @r << ")" << ;   Circle classMethod: newFromPoint(aPoint, r) self new(aPoint _x, aPoint _y, r) ;
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#ooRexx
ooRexx
  p = .point~new(3,2) c = .circle~new(,2,6)   p~print c~print   ::class point ::method init expose x y use strict arg x = 0, y = 0 -- defaults to 0 for any non-specified coordinates   ::attribute x ::attribute y   ::method print expose x y say "A point at location ("||x","y")"   ::class circle subclass point ::method init expose radius use strict arg x = 0, y = 0, radius = 0 self~init:super(x, y) -- call superclass constructor   ::attribute radius   ::method print expose radius say "A circle of radius" radius "centered at location ("||self~x","self~y")"    
http://rosettacode.org/wiki/Poker_hand_analyser
Poker hand analyser
Task Create a program to parse a single five card poker hand and rank it according to this list of poker hands. A poker hand is specified as a space separated list of five playing cards. Each input card has two characters indicating face and suit. Example 2d       (two of diamonds). Faces are:    a, 2, 3, 4, 5, 6, 7, 8, 9, 10, j, q, k Suits are:    h (hearts),   d (diamonds),   c (clubs),   and   s (spades),   or alternatively,   the unicode card-suit characters:    ♥ ♦ ♣ ♠ Duplicate cards are illegal. The program should analyze a single hand and produce one of the following outputs: straight-flush four-of-a-kind full-house flush straight three-of-a-kind two-pair one-pair high-card invalid Examples 2♥ 2♦ 2♣ k♣ q♦: three-of-a-kind 2♥ 5♥ 7♦ 8♣ 9♠: high-card a♥ 2♦ 3♣ 4♣ 5♦: straight 2♥ 3♥ 2♦ 3♣ 3♦: full-house 2♥ 7♥ 2♦ 3♣ 3♦: two-pair 2♥ 7♥ 7♦ 7♣ 7♠: four-of-a-kind 10♥ j♥ q♥ k♥ a♥: straight-flush 4♥ 4♠ k♠ 5♦ 10♠: one-pair q♣ 10♣ 7♣ 6♣ q♣: invalid The programs output for the above examples should be displayed here on this page. Extra credit use the playing card characters introduced with Unicode 6.0 (U+1F0A1 - U+1F0DE). allow two jokers use the symbol   joker duplicates would be allowed (for jokers only) five-of-a-kind would then be the highest hand More extra credit examples joker 2♦ 2♠ k♠ q♦: three-of-a-kind joker 5♥ 7♦ 8♠ 9♦: straight joker 2♦ 3♠ 4♠ 5♠: straight joker 3♥ 2♦ 3♠ 3♦: four-of-a-kind joker 7♥ 2♦ 3♠ 3♦: three-of-a-kind joker 7♥ 7♦ 7♠ 7♣: five-of-a-kind joker j♥ q♥ k♥ A♥: straight-flush joker 4♣ k♣ 5♦ 10♠: one-pair joker k♣ 7♣ 6♣ 4♣: flush joker 2♦ joker 4♠ 5♠: straight joker Q♦ joker A♠ 10♠: straight joker Q♦ joker A♦ 10♦: straight-flush joker 2♦ 2♠ joker q♦: four-of-a-kind Related tasks Playing cards Card shuffles Deal cards_for_FreeCell War Card_Game Go Fish
#Tcl
Tcl
package require Tcl 8.6 namespace eval PokerHandAnalyser { proc analyse {hand} { set norm [Normalise $hand] foreach type { invalid straight-flush four-of-a-kind full-house flush straight three-of-a-kind two-pair one-pair } { if {[Detect-$type $norm]} { return $type } } # Always possible to use high-card if the hand is legal at all return high-card }   # This normalises to an internal representation that is a list of pairs, # where each pair is one number for the pips (ace == 14, king == 13, # etc.) and another for the suit. This greatly simplifies detection. proc Normalise {hand} { set PipMap {j 11 q 12 k 13 a 14} set SuitMap {♥ 2 h 2 ♦ 1 d 1 ♣ 0 c 0 ♠ 3 s 3} set hand [string tolower $hand] set cards [regexp -all -inline {(?:[akqj98765432]|10)[hdcs♥♦♣♠]} $hand] lsort -command CompareCards [lmap c [string map {} $cards] { list [string map $PipMap [string range $c 0 end-1]] \ [string map $SuitMap [string index $c end]] }] } proc CompareCards {a b} { lassign $a pipA suitA lassign $b pipB suitB expr {$pipA==$pipB ? $suitB-$suitA : $pipB-$pipA} }   # Detection code. Note that the detectors all assume that the preceding # detectors have been run first; this simplifies the logic a lot, but does # mean that the individual detectors are not robust on their own. proc Detect-invalid {hand} { if {[llength $hand] != 5} {return 1} foreach c $hand { if {[incr seen($c)] > 1} {return 1} } return 0 } proc Detect-straight-flush {hand} { foreach c $hand { lassign $c pip suit if {[info exist prev] && $prev-1 != $pip} { # Special case: ace low straight flush ("steel wheel") if {$prev != 14 && $suit != 5} { return 0 } } set prev $pip incr seen($suit) } return [expr {[array size seen] == 1}] } proc Detect-four-of-a-kind {hand} { foreach c $hand { lassign $c pip suit if {[incr seen($pip)] > 3} {return 1} } return 0 } proc Detect-full-house {hand} { foreach c $hand { lassign $c pip suit incr seen($pip) } return [expr {[array size seen] == 2}] } proc Detect-flush {hand} { foreach c $hand { lassign $c pip suit incr seen($suit) } return [expr {[array size seen] == 1}] } proc Detect-straight {hand} { foreach c $hand { lassign $c pip suit if {[info exist prev] && $prev-1 != $pip} { # Special case: ace low straight ("wheel") if {$prev != 14 && $suit != 5} { return 0 } } set prev $pip } return 1 } proc Detect-three-of-a-kind {hand} { foreach c $hand { lassign $c pip suit if {[incr seen($pip)] > 2} {return 1} } return 0 } proc Detect-two-pair {hand} { set pairs 0 foreach c $hand { lassign $c pip suit if {[incr seen($pip)] > 1} {incr pairs} } return [expr {$pairs > 1}] } proc Detect-one-pair {hand} { foreach c $hand { lassign $c pip suit if {[incr seen($pip)] > 1} {return 1} } return 0 } }
http://rosettacode.org/wiki/Population_count
Population count
Population count You are encouraged to solve this task according to the task description, using any language you may know. The   population count   is the number of   1s   (ones)   in the binary representation of a non-negative integer. Population count   is also known as:   pop count   popcount   sideways sum   bit summation   Hamming weight For example,   5   (which is   101   in binary)   has a population count of   2. Evil numbers   are non-negative integers that have an   even   population count. Odious numbers     are  positive integers that have an    odd   population count. Task write a function (or routine) to return the population count of a non-negative integer. all computation of the lists below should start with   0   (zero indexed). display the   pop count   of the   1st   thirty powers of   3       (30,   31,   32,   33,   34,   ∙∙∙   329). display the   1st   thirty     evil     numbers. display the   1st   thirty   odious   numbers. display each list of integers on one line   (which may or may not include a title),   each set of integers being shown should be properly identified. See also The On-Line Encyclopedia of Integer Sequences:   A000120 population count. The On-Line Encyclopedia of Integer Sequences:   A000069 odious numbers. The On-Line Encyclopedia of Integer Sequences:   A001969 evil numbers.
#Idris
Idris
module Main import Data.Vect   isOdd : (x : Int) -> Bool isOdd x = case mod x 2 of 0 => False 1 => True   popcnt : Int -> Int popcnt 0 = 0 popcnt x = case isOdd x of False => popcnt (shiftR x 1) True => 1 + popcnt (shiftR x 1)   isOdious : Int -> Bool isOdious k = isOdd (popcnt k)   isEvil : Int -> Bool isEvil k = not (isOdious k)   filterUnfoldN : (n : Nat) -> (pred : Int -> Bool) -> (f : Int -> a) -> (next : Int -> Int) -> (seed : Int) -> Vect n a filterUnfoldN Z pred f next seed = [] filterUnfoldN (S k) pred f next seed = if pred seed then (f seed) :: filterUnfoldN k pred f next (next seed) else filterUnfoldN (S k) pred f next (next seed)   printCompact : (Show a) => Vect n a -> IO () printCompact v = putStrLn (unwords (map show (toList v)))   main : IO () main = do putStr "popcnt(3**i): " printCompact (filterUnfoldN 30 (\_ => True) popcnt (3 *) 1) putStr "Evil: " printCompact (filterUnfoldN 30 isEvil id (1 +) 0) putStr "Odious: " printCompact (filterUnfoldN 30 isOdious id (1 +) 0)
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#Smalltalk
Smalltalk
Object subclass: Polynomial [ |coeffs| Polynomial class >> new [ ^ super basicNew init ] init [ coeffs := OrderedCollection new. ^ self ] Polynomial class >> newWithCoefficients: coefficients [ |r| r := super basicNew. ^ r initWithCoefficients: coefficients ] initWithCoefficients: coefficients [ coeffs := coefficients asOrderedCollection. ^ self ] / denominator [ |n q| n := self deepCopy. self >= denominator ifTrue: [ q := Polynomial new. [ n >= denominator ] whileTrue: [ |piv| piv := (n coeff: 0) / (denominator coeff: 0). q addCoefficient: piv. n := n - (denominator * piv). n clean ]. ^ { q . (n degree) > 0 ifTrue: [ n ] ifFalse: [ n addCoefficient: 0. n ] } ] ifFalse: [ ^ { Polynomial newWithCoefficients: #( 0 ) . self deepCopy } ] ] * constant [ |r| r := self deepCopy. 1 to: (coeffs size) do: [ :i | r at: i put: ((r at: i) * constant) ]. ^ r ] at: index [ ^ coeffs at: index ] at: index put: obj [ ^ coeffs at: index put: obj ] >= anotherPoly [ ^ (self degree) >= (anotherPoly degree) ] degree [ ^ coeffs size ] - anotherPoly [ "This is not a real subtraction between Polynomial: it is an internal method ..." |a| a := self deepCopy. 1 to: ( (coeffs size) min: (anotherPoly degree) ) do: [ :i | a at: i put: ( (a at: i) - (anotherPoly at: i) ) ]. ^ a ] coeff: index [ ^ coeffs at: (index + 1) ] addCoefficient: coeff [ coeffs add: coeff ] clean [ [ (coeffs size) > 0 ifTrue: [ (coeffs at: 1) = 0 ] ifFalse: [ false ] ] whileTrue: [ coeffs removeFirst ]. ] display [ 1 to: (coeffs size) do: [ :i | (coeffs at: i) display. i < (coeffs size) ifTrue: [ ('x^%1 + ' % {(coeffs size) - i} ) display ] ] ] displayNl [ self display. Character nl display ] ].
http://rosettacode.org/wiki/Polynomial_regression
Polynomial regression
Find an approximating polynomial of known degree for a given data. Example: For input data: x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}; The approximating polynomial is: 3 x2 + 2 x + 1 Here, the polynomial's coefficients are (3, 2, 1). This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Raku
Raku
use Clifford;   constant @x1 = <0 1 2 3 4 5 6 7 8 9 10>; constant @y = <1 6 17 34 57 86 121 162 209 262 321>;   constant $x0 = [+] @e[^@x1]; constant $x1 = [+] @x1 Z* @e; constant $x2 = [+] @x1 »**» 2 Z* @e;   constant $y = [+] @y Z* @e;   my $J = $x1 ∧ $x2; my $I = $x0 ∧ $J;   my $I2 = ($I·$I.reversion).Real;   .say for (($y ∧ $J)·$I.reversion)/$I2, (($y ∧ ($x2 ∧ $x0))·$I.reversion)/$I2, (($y ∧ ($x0 ∧ $x1))·$I.reversion)/$I2;
http://rosettacode.org/wiki/Power_set
Power set
A   set   is a collection (container) of certain values, without any particular order, and no repeated values. It corresponds with a finite set in mathematics. A set can be implemented as an associative array (partial mapping) in which the value of each key-value pair is ignored. Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S. Task By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S. For example, the power set of     {1,2,3,4}     is {{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}. For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set. The power set of the empty set is the set which contains itself (20 = 1): P {\displaystyle {\mathcal {P}}} ( ∅ {\displaystyle \varnothing } ) = { ∅ {\displaystyle \varnothing } } And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2): P {\displaystyle {\mathcal {P}}} ({ ∅ {\displaystyle \varnothing } }) = { ∅ {\displaystyle \varnothing } , { ∅ {\displaystyle \varnothing } } } Extra credit: Demonstrate that your language supports these last two powersets.
#K
K
  ps:{x@&:'+2_vs!_2^#x}  
http://rosettacode.org/wiki/Primality_by_trial_division
Primality by trial division
Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops are allowed. Related tasks   count in factors   prime decomposition   AKS test for primes   factors of an integer   Sieve of Eratosthenes   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#ERRE
ERRE
PROGRAM PRIME_TRIAL   PROCEDURE ISPRIME(N%->OK%) LOCAL T% IF N%<=1 THEN OK%=FALSE EXIT PROCEDURE END IF IF N%<=3 THEN OK%=TRUE EXIT PROCEDURE END IF IF (N% AND 1)=0 THEN OK%=FALSE EXIT PROCEDURE END IF FOR T%=3 TO SQR(N%) STEP 2 DO IF N% MOD T%=0 THEN OK%=FALSE EXIT PROCEDURE END IF END FOR OK%=TRUE END PROCEDURE   BEGIN   FOR I%=1 TO 100 DO ISPRIME(I%->OK%) IF OK% THEN PRINT(i%;"is prime") END IF END FOR   END PROGRAM
http://rosettacode.org/wiki/Price_fraction
Price fraction
A friend of mine runs a pharmacy.   He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value.   This value is regulated by a government department. Task Given a floating point value between   0.00   and   1.00,   rescale according to the following table: >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00
#Oforth
Oforth
[.06, .11, .16, .21, .26, .31, .36, .41, .46, .51, .56, .61, .66, .71, .76, .81, .86, .91, .96, 1.01] const: IN [.10, .18, .26, .32, .38, .44, .50, .54, .58, .62, .66, .70, .74, .78, .82, .86, .90, .94, .98, 1.00] const: OUT   : priceFraction(f) | i | IN size loop: i [ f IN at(i) < ifTrue: [ OUT at(i) return ] ] null ;
http://rosettacode.org/wiki/Proper_divisors
Proper divisors
The   proper divisors   of a positive integer N are those numbers, other than N itself, that divide N without remainder. For N > 1 they will always include 1,   but for N == 1 there are no proper divisors. Examples The proper divisors of     6     are   1, 2, and 3. The proper divisors of   100   are   1, 2, 4, 5, 10, 20, 25, and 50. Task Create a routine to generate all the proper divisors of a number. use it to show the proper divisors of the numbers 1 to 10 inclusive. Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has. Show all output here. Related tasks   Amicable pairs   Abundant, deficient and perfect number classifications   Aliquot sequence classifications   Factors of an integer   Prime decomposition
#PureBasic
PureBasic
  EnableExplicit   Procedure ListProperDivisors(Number, List Lst()) If Number < 2 : ProcedureReturn : EndIf Protected i For i = 1 To Number / 2 If Number % i = 0 AddElement(Lst()) Lst() = i EndIf Next EndProcedure   Procedure.i CountProperDivisors(Number) If Number < 2 : ProcedureReturn 0 : EndIf Protected i, count = 0 For i = 1 To Number / 2 If Number % i = 0 count + 1 EndIf Next ProcedureReturn count EndProcedure   Define n, count, most = 1, maxCount = 0 If OpenConsole() PrintN("The proper divisors of the following numbers are : ") PrintN("") NewList lst() For n = 1 To 10 ListProperDivisors(n, lst()) Print(RSet(Str(n), 3) + " -> ") If ListSize(lst()) = 0 Print("(None)") Else ForEach lst() Print(Str(lst()) + " ") Next EndIf ClearList(lst()) PrintN("") Next For n = 2 To 20000 count = CountProperDivisors(n) If count > maxCount maxCount = count most = n EndIf Next PrintN("") PrintN(Str(most) + " has the most proper divisors, namely " + Str(maxCount)) PrintN("") PrintN("Press any key to close the console") Repeat: Delay(10) : Until Inkey() <> "" CloseConsole() EndIf  
http://rosettacode.org/wiki/Priority_queue
Priority queue
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order. Task Create a priority queue.   The queue must support at least two operations:   Insertion.   An element is added to the queue with a priority (a numeric value).   Top item removal.   Deletes the element or one of the elements with the current top priority and return it. Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc. To test your implementation, insert a number of elements into the queue, each with some random priority. Then dequeue them sequentially; now the elements should be sorted by priority. You can use the following task/priority items as input data: Priority Task ══════════ ════════════════ 3 Clear drains 4 Feed cat 5 Make tea 1 Solve RC tasks 2 Tax return The implementation should try to be efficient.   A typical implementation has   O(log n)   insertion and extraction time,   where   n   is the number of items in the queue. You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc.   If so, discuss the reasons behind it.
#Ruby
Ruby
class PriorityQueueNaive def initialize(data=nil) @q = Hash.new {|h, k| h[k] = []} data.each {|priority, item| @q[priority] << item} if data @priorities = @q.keys.sort end   def push(priority, item) @q[priority] << item @priorities = @q.keys.sort end   def pop p = @priorities[0] item = @q[p].shift if @q[p].empty? @q.delete(p) @priorities.shift end item end   def peek unless empty? @q[@priorities[0]][0] end end   def empty? @priorities.empty? end   def each @q.each do |priority, items| items.each {|item| yield priority, item} end end   def dup @q.each_with_object(self.class.new) do |(priority, items), obj| items.each {|item| obj.push(priority, item)} end end   def merge(other) raise TypeError unless self.class == other.class pq = dup other.each {|priority, item| pq.push(priority, item)} pq # return a new object end   def inspect @q.inspect end end   test = [ [6, "drink tea"], [3, "Clear drains"], [4, "Feed cat"], [5, "Make tea"], [6, "eat biscuit"], [1, "Solve RC tasks"], [2, "Tax return"], ]   pq = PriorityQueueNaive.new test.each {|pr, str| pq.push(pr, str) } until pq.empty? puts pq.pop end   puts test2 = test.shift(3) p pq1 = PriorityQueueNaive.new(test) p pq2 = PriorityQueueNaive.new(test2) p pq3 = pq1.merge(pq2) puts "peek : #{pq3.peek}" until pq3.empty? puts pq3.pop end puts "peek : #{pq3.peek}"
http://rosettacode.org/wiki/Prime_decomposition
Prime decomposition
The prime decomposition of a number is defined as a list of prime numbers which when all multiplied together, are equal to that number. Example 12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3} Task Write a function which returns an array or collection which contains the prime decomposition of a given number   n {\displaystyle n}   greater than   1. If your language does not have an isPrime-like function available, you may assume that you have a function which determines whether a number is prime (note its name before your code). If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes. Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc). Related tasks   count in factors   factors of an integer   Sieve of Eratosthenes   primality by trial division   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Lambdatalk
Lambdatalk
  {def prime_fact.smallest {def prime_fact.smallest.r {lambda {:q :r :i} {if {and {> :r 0} {< :i :q}} then {prime_fact.smallest.r :q {% :q {+ :i 1}} {+ :i 1}} else :i}}} {lambda {:q} {prime_fact.smallest.r :q {% :q 2} 2}}}   {def prime_fact {def prime_fact.r {lambda {:q :d} {if {> :q 1} then {let { {:q :q} {:d :d} {:i {prime_fact.smallest :q}}} {prime_fact.r {floor {/ :q :i}} {#.push! :d :i}} } else {if {= {#.length :d} 1} then {b :d} else :d}}}} {lambda {:n} :n:{prime_fact.r :n {#.new}}}}   {prime_fact {* 2 3 3 3 31 47 173}} -> 13611294:[2,3,3,3,31,47,173]   {map prime_fact {serie 2 101}} -> 2:[2] 3:[3] 4:[2,2] 5:[5] 6:[2,3] 7:[7] 8:[2,2,2] 9:[3,3] 10:[2,5] 11:[11] 12:[2,2,3] 13:[13] 14:[2,7] 15:[3,5] 16:[2,2,2,2] 17:[17] 18:[2,3,3] 19:[19] 20:[2,2,5] 21:[3,7] 22:[2,11] 23:[23] 24:[2,2,2,3] 25:[5,5] 26:[2,13] 27:[3,3,3] 28:[2,2,7] 29:[29] 30:[2,3,5] 31:[31] 32:[2,2,2,2,2] 33:[3,11] 34:[2,17] 35:[5,7] 36:[2,2,3,3] 37:[37] 38:[2,19] 39:[3,13] 40:[2,2,2,5] 41:[41] 42:[2,3,7] 43:[43] 44:[2,2,11] 45:[3,3,5] 46:[2,23] 47:[47] 48:[2,2,2,2,3] 49:[7,7] 50:[2,5,5] 51:[3,17] 52:[2,2,13] 53:[53] 54:[2,3,3,3] 55:[5,11] 56:[2,2,2,7] 57:[3,19] 58:[2,29] 59:[59] 60:[2,2,3,5] 61:[61] 62:[2,31] 63:[3,3,7] 64:[2,2,2,2,2,2] 65:[5,13] 66:[2,3,11] 67:[67] 68:[2,2,17] 69:[3,23] 70:[2,5,7] 71:[71] 72:[2,2,2,3,3] 73:[73] 74:[2,37] 75:[3,5,5] 76:[2,2,19] 77:[7,11] 78:[2,3,13] 79:[79] 80:[2,2,2,2,5] 81:[3,3,3,3] 82:[2,41] 83:[83] 84:[2,2,3,7] 85:[5,17] 86:[2,43] 87:[3,29] 88:[2,2,2,11] 89:[89] 90:[2,3,3,5] 91:[7,13] 92:[2,2,23] 93:[3,31] 94:[2,47] 95:[5,19] 96:[2,2,2,2,2,3] 97:[97] 98:[2,7,7] 99:[3,3,11] 100:[2,2,5,5] 101:[101]  
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#PicoLisp
PicoLisp
(load "@lib/ps.l")   (scl 1)   (de plot (PsFile DX DY Lst) (let (SX (length Lst) SY (apply max Lst) N 0 Val) (out PsFile (psHead (+ DX 20) (+ DY 40)) (font (9 . "Helvetica")) (if (or (=0 SX) (=0 SY)) (window 60 12 DX DY (font 24 ,"Not enough Data") ) (setq Lst # Build coordinates (let X -1 (mapcar '((Y) (cons (*/ (inc 'X) DX SX) (- DY (*/ Y DY SY)) ) ) Lst ) ) ) (color 55 95 55 # Background color (let (X (+ DX 40) Y (+ DY 40)) (poly T 0 0 X 0 X Y 0 Y 0 0) ) ) (window 20 20 DX DY # Plot coordinates (poly NIL 0 0 0 DY (- DX 20) DY) (color 76 24 24 (poly NIL (caar Lst) (cdar Lst) (cdr Lst)) ) ) (window 4 4 60 12 (ps (format SY *Scl))) (for X SX (window (+ 6 (*/ (dec X) DX SX)) (+ 24 DY) 30 12 (ps (format (dec X)) 0) ) ) ) (page) ) ) )   (plot "plot.ps" 300 200 (2.7 2.8 31.4 38.1 58.0 76.2 100.5 130.0 149.3 180.0)) (call 'display "plot.ps")
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#PostScript
PostScript
  /x [0 1 2 3 4 5 6 7 8 9] def /y [2.7 2.8 31.4 38.1 58.0 76.2 100.5 130.0 149.3 180.0] def /i 1 def   newpath x 0 get y 0 get moveto x length 1 sub{ x i get y i get lineto /i i 1 add def }repeat stroke  
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#OxygenBasic
OxygenBasic
  type tpoint float xx,yy type tcircle float xx,yy,rr   '========== class point '========== ' has tpoint ' method constructor (float x=0,y=0){this<=x,y} method destructor {} method V() as point {return @this} method V(tpoint*a) {this<=a.xx,a.yy} method V(point *a) {this<=a.xx,a.yy} method X() as float {return xx} method Y() as float {return yy} method X(float a) {xx=a} method Y(float a) {yy=a} method clear() {this<=.0,.0} method show() as string {return "x=" xx ", y=" yy } ' end class     '=========== class circle '=========== ' has point float rr ' method constructor (float x=.0,y=.0,r=1.0){this<=x,y,r} method V(tcircle*a) {this<=a.xx,a.yy,a.rr} method V(circle *a) {this<=a.xx,a.yy,a.rr} method R() as float {return rr} method R(float a) {rr=a} method clear() {this<=.0,.0,.0} method show() as string {return "x=" xx ", y=" yy ", r=" rr } ' end class   '===== 'TESTS '=====   new circle ca (r=.5) new circle cb (x=10,y=10) new circle cc (10,10,0.5)   cb.r="7.5" 'will convert a string value   cb.y=20   print cb.show 'result x=10, y=20 ,r=7.5   del ca : del cb : del cc  
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#Oz
Oz
class Point feat x y   meth init(x:X<=0.0 y:Y<=0.0) self.x = X self.y = Y end   meth print {System.showInfo "Point("# "x:"#self.x# ", y:"#self.y# ")"} end end   class Circle feat center r   meth init(center:C<={New Point init} r:R<=1.0) self.center = C self.r = R end   meth print {System.showInfo "Circle("# "x:"#self.center.x# ", y:"#self.center.y# ", r:"#self.r# ")"} end end
http://rosettacode.org/wiki/Poker_hand_analyser
Poker hand analyser
Task Create a program to parse a single five card poker hand and rank it according to this list of poker hands. A poker hand is specified as a space separated list of five playing cards. Each input card has two characters indicating face and suit. Example 2d       (two of diamonds). Faces are:    a, 2, 3, 4, 5, 6, 7, 8, 9, 10, j, q, k Suits are:    h (hearts),   d (diamonds),   c (clubs),   and   s (spades),   or alternatively,   the unicode card-suit characters:    ♥ ♦ ♣ ♠ Duplicate cards are illegal. The program should analyze a single hand and produce one of the following outputs: straight-flush four-of-a-kind full-house flush straight three-of-a-kind two-pair one-pair high-card invalid Examples 2♥ 2♦ 2♣ k♣ q♦: three-of-a-kind 2♥ 5♥ 7♦ 8♣ 9♠: high-card a♥ 2♦ 3♣ 4♣ 5♦: straight 2♥ 3♥ 2♦ 3♣ 3♦: full-house 2♥ 7♥ 2♦ 3♣ 3♦: two-pair 2♥ 7♥ 7♦ 7♣ 7♠: four-of-a-kind 10♥ j♥ q♥ k♥ a♥: straight-flush 4♥ 4♠ k♠ 5♦ 10♠: one-pair q♣ 10♣ 7♣ 6♣ q♣: invalid The programs output for the above examples should be displayed here on this page. Extra credit use the playing card characters introduced with Unicode 6.0 (U+1F0A1 - U+1F0DE). allow two jokers use the symbol   joker duplicates would be allowed (for jokers only) five-of-a-kind would then be the highest hand More extra credit examples joker 2♦ 2♠ k♠ q♦: three-of-a-kind joker 5♥ 7♦ 8♠ 9♦: straight joker 2♦ 3♠ 4♠ 5♠: straight joker 3♥ 2♦ 3♠ 3♦: four-of-a-kind joker 7♥ 2♦ 3♠ 3♦: three-of-a-kind joker 7♥ 7♦ 7♠ 7♣: five-of-a-kind joker j♥ q♥ k♥ A♥: straight-flush joker 4♣ k♣ 5♦ 10♠: one-pair joker k♣ 7♣ 6♣ 4♣: flush joker 2♦ joker 4♠ 5♠: straight joker Q♦ joker A♠ 10♠: straight joker Q♦ joker A♦ 10♦: straight-flush joker 2♦ 2♠ joker q♦: four-of-a-kind Related tasks Playing cards Card shuffles Deal cards_for_FreeCell War Card_Game Go Fish
#Wren
Wren
import "/dynamic" for Tuple import "/sort" for Sort import "/str" for Str import "/seq" for Lst   var Card = Tuple.create("Card", ["face", "suit"])   var FACES = "23456789tjqka" var SUITS = "shdc"   var isStraight = Fn.new { |cards| var cmp = Fn.new { |i, j| (i.face - j.face).sign } var sorted = Sort.merge(cards, cmp) if (sorted[0].face + 4 == sorted[4].face) return true if (sorted[4].face == 14 && sorted[0].face == 2 && sorted[3].face == 5) return true return false }   var isFlush = Fn.new { |cards| var suit = cards[0].suit if (cards.skip(1).all { |card| card.suit == suit }) return true return false }   var analyzeHand = Fn.new { |hand| var h = Str.lower(hand) var split = Lst.distinct(h.split(" ").where { |c| c != "" }.toList) if (split.count != 5) return "invalid" var cards = [] for (s in split) { if (s.count != 2) return "invalid" var fIndex = FACES.indexOf(s[0]) if (fIndex == -1) return "invalid" var sIndex = SUITS.indexOf(s[1]) if (sIndex == -1) return "invalid" cards.add(Card.new(fIndex + 2, s[1])) } var groups = Lst.groups(cards) { |card| card.face } if (groups.count == 2) { if (groups.any { |g| g[1].count == 4 }) return "four-of-a-kind" return "full-house" } else if (groups.count == 3) { if (groups.any { |g| g[1].count == 3 }) return "three-of-a-kind" return "two-pair" } else if (groups.count == 4) { return "one-pair" } else { var flush = isFlush.call(cards) var straight = isStraight.call(cards) if (flush && straight) return "straight-flush" if (flush) return "flush" if (straight) return "straight" return "high-card" } }   var hands = [ "2h 2d 2c kc qd", "2h 5h 7d 8c 9s", "ah 2d 3c 4c 5d", "2h 3h 2d 3c 3d", "2h 7h 2d 3c 3d", "2h 7h 7d 7c 7s", "th jh qh kh ah", "4h 4s ks 5d ts", "qc tc 7c 6c 4c", "ah ah 7c 6c 4c" ] for (hand in hands) { System.print("%(hand): %(analyzeHand.call(hand))") }
http://rosettacode.org/wiki/Population_count
Population count
Population count You are encouraged to solve this task according to the task description, using any language you may know. The   population count   is the number of   1s   (ones)   in the binary representation of a non-negative integer. Population count   is also known as:   pop count   popcount   sideways sum   bit summation   Hamming weight For example,   5   (which is   101   in binary)   has a population count of   2. Evil numbers   are non-negative integers that have an   even   population count. Odious numbers     are  positive integers that have an    odd   population count. Task write a function (or routine) to return the population count of a non-negative integer. all computation of the lists below should start with   0   (zero indexed). display the   pop count   of the   1st   thirty powers of   3       (30,   31,   32,   33,   34,   ∙∙∙   329). display the   1st   thirty     evil     numbers. display the   1st   thirty   odious   numbers. display each list of integers on one line   (which may or may not include a title),   each set of integers being shown should be properly identified. See also The On-Line Encyclopedia of Integer Sequences:   A000120 population count. The On-Line Encyclopedia of Integer Sequences:   A000069 odious numbers. The On-Line Encyclopedia of Integer Sequences:   A001969 evil numbers.
#J
J
countPopln=: +/"1@#: isOdd=: 1 = 2&| isEven=: 0 = 2&|
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#SPAD
SPAD
(1) -> monicDivide(x^3-12*x^2-42,x-3,'x)   2 (1) [quotient = x - 9x - 27,remainder = - 123]   Type: Record(quotient: Polynomial(Integer),remainder: Polynomial(Integer))
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#Swift
Swift
protocol Dividable { static func / (lhs: Self, rhs: Self) -> Self }   extension Int: Dividable { }   struct Solution<T> { var quotient: [T] var remainder: [T] }   func polyDegree<T: SignedNumeric>(_ p: [T]) -> Int { for i in stride(from: p.count - 1, through: 0, by: -1) where p[i] != 0 { return i }   return Int.min }   func polyShiftRight<T: SignedNumeric>(p: [T], places: Int) -> [T] { guard places > 0 else { return p }   let deg = polyDegree(p)   assert(deg + places < p.count, "Number of places to shift too large")   var res = p   for i in stride(from: deg, through: 0, by: -1) { res[i + places] = res[i] res[i] = 0 }   return res }   func polyMul<T: SignedNumeric>(_ p: inout [T], by: T) { for i in 0..<p.count { p[i] *= by } }   func polySub<T: SignedNumeric>(_ p: inout [T], by: [T]) { for i in 0..<p.count { p[i] -= by[i] } }   func polyLongDiv<T: SignedNumeric & Dividable>(numerator n: [T], denominator d: [T]) -> Solution<T>? { guard n.count == d.count else { return nil }   var nDeg = polyDegree(n) let dDeg = polyDegree(d)   guard dDeg >= 0, nDeg >= dDeg else { return nil }   var n2 = n var quo = [T](repeating: 0, count: n.count)   while nDeg >= dDeg { let i = nDeg - dDeg var d2 = polyShiftRight(p: d, places: i)   quo[i] = n2[nDeg] / d2[nDeg]   polyMul(&d2, by: quo[i]) polySub(&n2, by: d2)   nDeg = polyDegree(n2) }   return Solution(quotient: quo, remainder: n2) }   func polyPrint<T: SignedNumeric & Comparable>(_ p: [T]) { let deg = polyDegree(p)   for i in stride(from: deg, through: 0, by: -1) where p[i] != 0 { let coeff = p[i]   switch coeff { case 1 where i < deg: print(" + ", terminator: "") case 1: print("", terminator: "") case -1 where i < deg: print(" - ", terminator: "") case -1: print("-", terminator: "") case _ where coeff < 0 && i < deg: print(" - \(-coeff)", terminator: "") case _ where i < deg: print(" + \(coeff)", terminator: "") case _: print("\(coeff)", terminator: "") }   if i > 1 { print("x^\(i)", terminator: "") } else if i == 1 { print("x", terminator: "") } }   print() }   let n = [-42, 0, -12, 1] let d = [-3, 1, 0, 0]   print("Numerator: ", terminator: "") polyPrint(n) print("Denominator: ", terminator: "") polyPrint(d)   guard let sol = polyLongDiv(numerator: n, denominator: d) else { fatalError() }   print("----------") print("Quotient: ", terminator: "") polyPrint(sol.quotient) print("Remainder: ", terminator: "") polyPrint(sol.remainder)
http://rosettacode.org/wiki/Polynomial_regression
Polynomial regression
Find an approximating polynomial of known degree for a given data. Example: For input data: x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}; The approximating polynomial is: 3 x2 + 2 x + 1 Here, the polynomial's coefficients are (3, 2, 1). This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#REXX
REXX
/* REXX --------------------------------------------------------------- * Implementation of http://keisan.casio.com/exec/system/14059932254941 *--------------------------------------------------------------------*/ xl='0 1 2 3 4 5 6 7 8 9 10' yl='1 6 17 34 57 86 121 162 209 262 321' n=11 Do i=1 To n Parse Var xl x.i xl Parse Var yl y.i yl End xm=0 ym=0 x2m=0 x3m=0 x4m=0 xym=0 x2ym=0 Do i=1 To n xm=xm+x.i ym=ym+y.i x2m=x2m+x.i**2 x3m=x3m+x.i**3 x4m=x4m+x.i**4 xym=xym+x.i*y.i x2ym=x2ym+(x.i**2)*y.i End xm =xm /n ym =ym /n x2m=x2m/n x3m=x3m/n x4m=x4m/n xym=xym/n x2ym=x2ym/n Sxx=x2m-xm**2 Sxy=xym-xm*ym Sxx2=x3m-xm*x2m Sx2x2=x4m-x2m**2 Sx2y=x2ym-x2m*ym B=(Sxy*Sx2x2-Sx2y*Sxx2)/(Sxx*Sx2x2-Sxx2**2) C=(Sx2y*Sxx-Sxy*Sxx2)/(Sxx*Sx2x2-Sxx2**2) A=ym-B*xm-C*x2m Say 'y='a'+'||b'*x+'c'*x**2' Say ' Input "Approximation"' Say ' x y y1' Do i=1 To 11 Say right(x.i,2) right(y.i,3) format(fun(x.i),5,3) End Exit fun: Parse Arg x Return a+b*x+c*x**2
http://rosettacode.org/wiki/Power_set
Power set
A   set   is a collection (container) of certain values, without any particular order, and no repeated values. It corresponds with a finite set in mathematics. A set can be implemented as an associative array (partial mapping) in which the value of each key-value pair is ignored. Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S. Task By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S. For example, the power set of     {1,2,3,4}     is {{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}. For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set. The power set of the empty set is the set which contains itself (20 = 1): P {\displaystyle {\mathcal {P}}} ( ∅ {\displaystyle \varnothing } ) = { ∅ {\displaystyle \varnothing } } And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2): P {\displaystyle {\mathcal {P}}} ({ ∅ {\displaystyle \varnothing } }) = { ∅ {\displaystyle \varnothing } , { ∅ {\displaystyle \varnothing } } } Extra credit: Demonstrate that your language supports these last two powersets.
#Kotlin
Kotlin
// purely functional & lazy version, leveraging recursion and Sequences (a.k.a. streams) fun <T> Set<T>.subsets(): Sequence<Set<T>> = when (size) { 0 -> sequenceOf(emptySet()) else -> { val head = first() val tail = this - head tail.subsets() + tail.subsets().map { setOf(head) + it } } }   // if recursion is an issue, you may change it this way:   fun <T> Set<T>.subsets(): Sequence<Set<T>> = sequence { when (size) { 0 -> yield(emptySet<T>()) else -> { val head = first() val tail = this@subsets - head yieldAll(tail.subsets()) for (subset in tail.subsets()) { yield(setOf(head) + subset) } } } }  
http://rosettacode.org/wiki/Primality_by_trial_division
Primality by trial division
Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops are allowed. Related tasks   count in factors   prime decomposition   AKS test for primes   factors of an integer   Sieve of Eratosthenes   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Euphoria
Euphoria
function is_prime(integer n) if n<=2 or remainder(n,2)=0 then return 0 else for i=3 to sqrt(n) by 2 do if remainder(n,i)=0 then return 0 end if end for return 1 end if end function
http://rosettacode.org/wiki/Price_fraction
Price fraction
A friend of mine runs a pharmacy.   He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value.   This value is regulated by a government department. Task Given a floating point value between   0.00   and   1.00,   rescale according to the following table: >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00
#Oz
Oz
fun {PriceFraction X} OutOfRange = {Value.failed outOfRange(X)} in for Limit#Result in [0.00#OutOfRange 0.06#0.10 0.11#0.18 0.16#0.26 0.21#0.32 0.26#0.38 0.31#0.44 0.36#0.5 0.41#0.54 0.46#0.58 0.51#0.62 0.56#0.66 0.61#0.70 0.66#0.74 0.71#0.78 0.76#0.82 0.81#0.86 0.86#0.90 0.91#0.94 0.96#0.98 1.01#1.00 ] return:Return default:OutOfRange do if X < Limit then {Return Result} end end end
http://rosettacode.org/wiki/Proper_divisors
Proper divisors
The   proper divisors   of a positive integer N are those numbers, other than N itself, that divide N without remainder. For N > 1 they will always include 1,   but for N == 1 there are no proper divisors. Examples The proper divisors of     6     are   1, 2, and 3. The proper divisors of   100   are   1, 2, 4, 5, 10, 20, 25, and 50. Task Create a routine to generate all the proper divisors of a number. use it to show the proper divisors of the numbers 1 to 10 inclusive. Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has. Show all output here. Related tasks   Amicable pairs   Abundant, deficient and perfect number classifications   Aliquot sequence classifications   Factors of an integer   Prime decomposition
#Python
Python
>>> def proper_divs2(n): ... return {x for x in range(1, (n + 1) // 2 + 1) if n % x == 0 and n != x} ... >>> [proper_divs2(n) for n in range(1, 11)] [set(), {1}, {1}, {1, 2}, {1}, {1, 2, 3}, {1}, {1, 2, 4}, {1, 3}, {1, 2, 5}] >>> >>> n, length = max(((n, len(proper_divs2(n))) for n in range(1, 20001)), key=lambda pd: pd[1]) >>> n 15120 >>> length 79 >>>
http://rosettacode.org/wiki/Priority_queue
Priority queue
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order. Task Create a priority queue.   The queue must support at least two operations:   Insertion.   An element is added to the queue with a priority (a numeric value).   Top item removal.   Deletes the element or one of the elements with the current top priority and return it. Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc. To test your implementation, insert a number of elements into the queue, each with some random priority. Then dequeue them sequentially; now the elements should be sorted by priority. You can use the following task/priority items as input data: Priority Task ══════════ ════════════════ 3 Clear drains 4 Feed cat 5 Make tea 1 Solve RC tasks 2 Tax return The implementation should try to be efficient.   A typical implementation has   O(log n)   insertion and extraction time,   where   n   is the number of items in the queue. You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc.   If so, discuss the reasons behind it.
#Run_BASIC
Run BASIC
sqliteconnect #mem, ":memory:" #mem execute("CREATE TABLE queue (priority float,descr text)")   ' -------------------------------------------------------------- ' Insert items into the que ' -------------------------------------------------------------- #mem execute("INSERT INTO queue VALUES (3,'Clear drains')") #mem execute("INSERT INTO queue VALUES (4,'Feed cat')") #mem execute("INSERT INTO queue VALUES (5,'Make tea')") #mem execute("INSERT INTO queue VALUES (1,'Solve RC tasks')") #mem execute("INSERT INTO queue VALUES (2,'Tax return')")   '--------------- insert priority between 4 and 5 ----------------- #mem execute("INSERT INTO queue VALUES (4.5,'My Special Project')")   what$ = " -------------- Find first priority ---------------------" mem$ = "SELECT * FROM queue ORDER BY priority LIMIT 1" gosub [getQueue]   what$ = " -------------- Find last priority ---------------------" mem$ = "SELECT * FROM queue ORDER BY priority desc LIMIT 1" gosub [getQueue]   what$ = " -------------- Delete Highest Priority ---------------------" mem$ = "DELETE FROM queue WHERE priority = (select max(q.priority) FROM queue as q)" #mem execute(mem$)   what$ = " -------------- List Priority Sequence ---------------------" mem$ = "SELECT * FROM queue ORDER BY priority" gosub [getQueue] end     [getQueue] print what$ #mem execute(mem$) rows = #mem ROWCOUNT() print "Priority Description" for i = 1 to rows #row = #mem #nextrow() priority = #row priority() descr$ = #row descr$() print priority;" ";descr$ next i RETURN
http://rosettacode.org/wiki/Prime_decomposition
Prime decomposition
The prime decomposition of a number is defined as a list of prime numbers which when all multiplied together, are equal to that number. Example 12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3} Task Write a function which returns an array or collection which contains the prime decomposition of a given number   n {\displaystyle n}   greater than   1. If your language does not have an isPrime-like function available, you may assume that you have a function which determines whether a number is prime (note its name before your code). If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes. Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc). Related tasks   count in factors   factors of an integer   Sieve of Eratosthenes   primality by trial division   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#LFE
LFE
  (defun factors (n) (factors n 2 '()))   (defun factors ((1 _ acc) acc) ((n k acc) (when (== 0 (rem n k))) (factors (div n k) k (cons k acc))) ((n k acc) (factors n (+ k 1) acc)))  
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#PureBasic
PureBasic
Structure PlotData x.i y.f EndStructure   Global i, x, y.f, max_x, max_y, min_x = #MAXLONG, min_y = Infinity() Define count = (?serie_y - ?serie_x) / SizeOf(Integer) - 1 Global Dim MyData.PlotData(count)   Restore serie_x For i = 0 To count Read.i x MyData(i)\x = x If x > max_x: max_x = x: EndIf If x < min_x: min_x = x: EndIf Next Restore serie_y For i = 0 To count Read.f y MyData(i)\y = y If y > max_y: max_y = y: EndIf If y < min_y: min_y = y: EndIf Next   Procedure UpdatePlot(Win, w, h) Static gblm = 20, gtrm = 5 ;graph's bottom-left and top-right margin   Protected count = ArraySize(MyData()) If w > gblm And h > gblm And count > 0 SetWindowTitle(Win, "PureBasic Plot " + Str(w) + "x" + Str(h)) Protected gw = w - gblm, gh = h - gblm ;graph's width and height Protected i, yf.f, xf.f yf = (gh - gtrm) / max_y xf = (gw - gtrm) / max_x   CreateImage(0, w, h) Protected OutputID = ImageOutput(0) StartDrawing(OutputID) DrawingMode(#PB_2DDrawing_Transparent) ;- Draw grid For i = 0 To count y = gh - max_y * i / count * yf LineXY(gblm, y, w - gtrm, y, $467E3E) ; Y-scale DrawText(1, y - 5, RSet(StrD(i / count * max_y, 1), 5)) x = gblm + max_x * i / count * xf y = gh ; X-Scale LineXY(x, y, x, gtrm, $467E3E) If i: DrawText(x - 5, y + 2, Str(i)): EndIf Next   ;- Draw curve Protected ox = gblm, oy = gh, x, y For i = 0 To count x = gblm + MyData(i)\x * xf y = gh - MyData(i)\y * yf LineXY(ox, oy, x, y, $0133EE) ox = x: oy = y Next StopDrawing() ImageGadget(0, 0, 0, w, h, ImageID(0)) EndIf EndProcedure   Define Win = OpenWindow(#PB_Any, 0, 0, 600, 400,"", #PB_Window_SystemMenu | #PB_Window_SizeGadget) If Win SmartWindowRefresh(Win, 1) UpdatePlot(Win, WindowWidth(Win), WindowHeight(Win)) Repeat Define event = WaitWindowEvent() Select event Case #PB_Event_SizeWindow UpdatePlot(Win, WindowWidth(Win), WindowHeight(Win)) EndSelect Until event = #PB_Event_CloseWindow   ; Save the plot if the user wants to If MessageRequester("Question", "Save it?", #PB_MessageRequester_YesNo) = #PB_MessageRequester_Yes Define File$=SaveFileRequester("Save as", "PB.png", "PNG (*.png)|*.png", 0) UsePNGImageEncoder() SaveImage(0, File$, #PB_ImagePlugin_PNG) EndIf EndIf   DataSection serie_x: Data.i 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 serie_y: Data.f 2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0 EndDataSection
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#Pascal
Pascal
{ package Point; use Class::Spiffy -base; use Clone qw(clone);   sub _print { my %self = %{shift()}; while (my ($k,$v) = each %self) { print "$k: $v\n"; } }   sub members { no strict; grep { 1 == length and defined *$_{CODE} } keys %{*{__PACKAGE__."\::"}}; }   sub new { my $class = shift; my %param = @_; $param{$_} = 0 for grep {!defined $param{$_}} members; bless \%param, $class; }   sub copy_constructor { clone shift; }   sub copy_assignment { my $self = shift; my $from = shift; $self->$_($from->$_) for $from->members; }   field 'x'; field 'y'; }   { package Circle; use base qw(Point); field 'r'; }   { package main; $_->_print, print "\n" for ( Point->new, Point->new(x => 2), Point->new(y => 3), Point->new(x => 8, y => -5), ); my $p1 = Point->new(x => 8, y => -5);   my $p2 = $p1->copy_constructor; print "we are really different objects, not just references ". "to the same instance\n" unless \$p1 eq \$p2;   # accessors autogenerated $p1->x(1); $p1->y(2); print $p1->x, "\n"; print $p1->y, "\n";   $p2->copy_assignment($p1); print $p2->x, "\n"; print $p2->y, "\n"; print "we now have the same values, but we are still ". "different objects\n" unless \$p1 eq \$p2;   $_->_print, print "\n" for ( Circle->new, Circle->new(x => 1), Circle->new(y => 2), Circle->new(r => 3), Circle->new(x => 4, y => 5), Circle->new(x => 6, r => 7), Circle->new(y => 8, r => 9), Circle->new(x => 1, y => 2, r => 3), );   my $c = Circle->new(r => 4); print $c->r, "\n"; # accessor autogenerated }
http://rosettacode.org/wiki/Population_count
Population count
Population count You are encouraged to solve this task according to the task description, using any language you may know. The   population count   is the number of   1s   (ones)   in the binary representation of a non-negative integer. Population count   is also known as:   pop count   popcount   sideways sum   bit summation   Hamming weight For example,   5   (which is   101   in binary)   has a population count of   2. Evil numbers   are non-negative integers that have an   even   population count. Odious numbers     are  positive integers that have an    odd   population count. Task write a function (or routine) to return the population count of a non-negative integer. all computation of the lists below should start with   0   (zero indexed). display the   pop count   of the   1st   thirty powers of   3       (30,   31,   32,   33,   34,   ∙∙∙   329). display the   1st   thirty     evil     numbers. display the   1st   thirty   odious   numbers. display each list of integers on one line   (which may or may not include a title),   each set of integers being shown should be properly identified. See also The On-Line Encyclopedia of Integer Sequences:   A000120 population count. The On-Line Encyclopedia of Integer Sequences:   A000069 odious numbers. The On-Line Encyclopedia of Integer Sequences:   A001969 evil numbers.
#Java
Java
import java.math.BigInteger;   public class PopCount { public static void main(String[] args) { { // with int System.out.print("32-bit integer: "); int n = 1; for (int i = 0; i < 20; i++) { System.out.printf("%d ", Integer.bitCount(n)); n *= 3; } System.out.println(); } { // with long System.out.print("64-bit integer: "); long n = 1; for (int i = 0; i < 30; i++) { System.out.printf("%d ", Long.bitCount(n)); n *= 3; } System.out.println(); } { // with BigInteger System.out.print("big integer  : "); BigInteger n = BigInteger.ONE; BigInteger three = BigInteger.valueOf(3); for (int i = 0; i < 30; i++) { System.out.printf("%d ", n.bitCount()); n = n.multiply(three); } System.out.println(); }   int[] od = new int[30]; int ne = 0, no = 0; System.out.print("evil  : "); for (int n = 0; ne+no < 60; n++) { if ((Integer.bitCount(n) & 1) == 0) { if (ne < 30) { System.out.printf("%d ", n); ne++; } } else { if (no < 30) { od[no++] = n; } } } System.out.println(); System.out.print("odious : "); for (int n : od) { System.out.printf("%d ", n); } System.out.println(); } }
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#Tcl
Tcl
# poldiv - Divide two polynomials n and d. # Result is a list of two polynomials, q and r, where n = qd + r # and the degree of r is less than the degree of b. # Polynomials are represented as lists, where element 0 is the # x**0 coefficient, element 1 is the x**1 coefficient, and so on.   proc poldiv {a b} { # Toss out leading zero coefficients efficiently while {[lindex $a end] == 0} {set a [lrange $a[set a {}] 0 end-1]} while {[lindex $b end] == 0} {set b [lrange $b[set b {}] 0 end-1]} if {[llength $a] < [llength $b]} { return [list 0 $a] }   # Rearrange the terms to put highest powers first set n [lreverse $a] set d [lreverse $b]   # Carry out classical long division, accumulating quotient coefficients # in q, and replacing n with the remainder. set q {} while {[llength $n] >= [llength $d]} { set qd [expr {[lindex $n 0] / [lindex $d 0]}] set i 0 foreach nd [lrange $n 0 [expr {[llength $d] - 1}]] dd $d { lset n $i [expr {$nd - $qd * $dd}] incr i } lappend q $qd set n [lrange $n 1 end] }   # Return quotient and remainder, constant term first return [list [lreverse $q] [lreverse $n]] }   # Demonstration lassign [poldiv {-42. 0. -12. 1.} {-3. 1. 0. 0.}] Q R puts [list Q = $Q] puts [list R = $R]
http://rosettacode.org/wiki/Polynomial_regression
Polynomial regression
Find an approximating polynomial of known degree for a given data. Example: For input data: x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}; The approximating polynomial is: 3 x2 + 2 x + 1 Here, the polynomial's coefficients are (3, 2, 1). This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Ruby
Ruby
require 'matrix'   def regress x, y, degree x_data = x.map { |xi| (0..degree).map { |pow| (xi**pow).to_r } }   mx = Matrix[*x_data] my = Matrix.column_vector(y)   ((mx.t * mx).inv * mx.t * my).transpose.to_a[0].map(&:to_f) end
http://rosettacode.org/wiki/Power_set
Power set
A   set   is a collection (container) of certain values, without any particular order, and no repeated values. It corresponds with a finite set in mathematics. A set can be implemented as an associative array (partial mapping) in which the value of each key-value pair is ignored. Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S. Task By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S. For example, the power set of     {1,2,3,4}     is {{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}. For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set. The power set of the empty set is the set which contains itself (20 = 1): P {\displaystyle {\mathcal {P}}} ( ∅ {\displaystyle \varnothing } ) = { ∅ {\displaystyle \varnothing } } And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2): P {\displaystyle {\mathcal {P}}} ({ ∅ {\displaystyle \varnothing } }) = { ∅ {\displaystyle \varnothing } , { ∅ {\displaystyle \varnothing } } } Extra credit: Demonstrate that your language supports these last two powersets.
#Logo
Logo
to powerset :set if empty? :set [output [[]]] localmake "rest powerset butfirst :set output sentence map [sentence first :set ?] :rest  :rest end   show powerset [1 2 3] [[1 2 3] [1 2] [1 3] [1] [2 3] [2] [3] []]
http://rosettacode.org/wiki/Primality_by_trial_division
Primality by trial division
Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops are allowed. Related tasks   count in factors   prime decomposition   AKS test for primes   factors of an integer   Sieve of Eratosthenes   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#F.23
F#
open NUnit.Framework open FsUnit let inline isPrime n = not ({uint64 2..uint64 (sqrt (double n))} |> Seq.exists (fun (i:uint64) -> uint64 n % i = uint64 0)) [<Test>] let ``Validate that 2 is prime`` () = isPrime 2 |> should equal true   [<Test>] let ``Validate that 4 is not prime`` () = isPrime 4 |> should equal false   [<Test>] let ``Validate that 3 is prime`` () = isPrime 3 |> should equal true   [<Test>] let ``Validate that 9 is not prime`` () = isPrime 9 |> should equal false   [<Test>] let ``Validate that 5 is prime`` () = isPrime 5 |> should equal true   [<Test>] let ``Validate that 277 is prime`` () = isPrime 277 |> should equal true
http://rosettacode.org/wiki/Price_fraction
Price fraction
A friend of mine runs a pharmacy.   He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value.   This value is regulated by a government department. Task Given a floating point value between   0.00   and   1.00,   rescale according to the following table: >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00
#PARI.2FGP
PARI/GP
priceLookup=[6,11,16,21,26,31,41,46,51,56,61,66,71,76,81,86,91,96,101]; priceReplace=[10,18,26,32,38,44,50,54,58,62,66,70,74,78,82,86,90,94,98,100]; pf(x)={ x*=100; for(i=1,19, if(x<priceLookup[i], return(priceReplace[i])) ); "nasal demons" };
http://rosettacode.org/wiki/Proper_divisors
Proper divisors
The   proper divisors   of a positive integer N are those numbers, other than N itself, that divide N without remainder. For N > 1 they will always include 1,   but for N == 1 there are no proper divisors. Examples The proper divisors of     6     are   1, 2, and 3. The proper divisors of   100   are   1, 2, 4, 5, 10, 20, 25, and 50. Task Create a routine to generate all the proper divisors of a number. use it to show the proper divisors of the numbers 1 to 10 inclusive. Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has. Show all output here. Related tasks   Amicable pairs   Abundant, deficient and perfect number classifications   Aliquot sequence classifications   Factors of an integer   Prime decomposition
#Quackery
Quackery
[ factors -1 split drop ] is properdivisors ( n --> [ )   10 times [ i^ 1+ properdivisors echo cr ]   0 0 20000 times [ i^ 1+ properdivisors size 2dup < iff [ dip [ 2drop i^ 1+ ] ] else drop ] swap echo say " has " echo say " proper divisors." cr
http://rosettacode.org/wiki/Priority_queue
Priority queue
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order. Task Create a priority queue.   The queue must support at least two operations:   Insertion.   An element is added to the queue with a priority (a numeric value).   Top item removal.   Deletes the element or one of the elements with the current top priority and return it. Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc. To test your implementation, insert a number of elements into the queue, each with some random priority. Then dequeue them sequentially; now the elements should be sorted by priority. You can use the following task/priority items as input data: Priority Task ══════════ ════════════════ 3 Clear drains 4 Feed cat 5 Make tea 1 Solve RC tasks 2 Tax return The implementation should try to be efficient.   A typical implementation has   O(log n)   insertion and extraction time,   where   n   is the number of items in the queue. You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc.   If so, discuss the reasons behind it.
#Rust
Rust
use std::collections::BinaryHeap; use std::cmp::Ordering; use std::borrow::Cow;   #[derive(Eq, PartialEq)] struct Item<'a> { priority: usize, task: Cow<'a, str>, // Takes either borrowed or owned string }   impl<'a> Item<'a> { fn new<T>(p: usize, t: T) -> Self where T: Into<Cow<'a, str>> { Item { priority: p, task: t.into(), } } }   // Manually implpement Ord so we have a min heap impl<'a> Ord for Item<'a> { fn cmp(&self, other: &Self) -> Ordering { other.priority.cmp(&self.priority) } }   // PartialOrd is required by Ord impl<'a> PartialOrd for Item<'a> { fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(self.cmp(other)) } }     fn main() { let mut queue = BinaryHeap::with_capacity(5); queue.push(Item::new(3, "Clear drains")); queue.push(Item::new(4, "Feed cat")); queue.push(Item::new(5, "Make tea")); queue.push(Item::new(1, "Solve RC tasks")); queue.push(Item::new(2, "Tax return"));   for item in queue { println!("{}", item.task); } }
http://rosettacode.org/wiki/Prime_decomposition
Prime decomposition
The prime decomposition of a number is defined as a list of prime numbers which when all multiplied together, are equal to that number. Example 12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3} Task Write a function which returns an array or collection which contains the prime decomposition of a given number   n {\displaystyle n}   greater than   1. If your language does not have an isPrime-like function available, you may assume that you have a function which determines whether a number is prime (note its name before your code). If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes. Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc). Related tasks   count in factors   factors of an integer   Sieve of Eratosthenes   primality by trial division   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Lingo
Lingo
-- Returns list of prime factors for given number. -- To overcome the limits of integers (signed 32-bit in Lingo), -- the number can be specified as float (which works up to 2^53). -- For the same reason, values in returned list are floats, not integers. on getPrimeFactors (n) f = [] f.sort() c = sqrt(n) i = 1.0 repeat while TRUE i=i+1 if i>c then exit repeat check = n/i if bitOr(check,0)=check then f.add(i) n = check c = sqrt(n) i = 1.0 end if end repeat f.add(n) return f end
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Python
Python
>>> x = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] >>> y = [2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0]   >>> import pylab >>> pylab.plot(x, y, 'bo') >>> pylab.savefig('qsort-range-10-9.png')  
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#Perl
Perl
{ package Point; use Class::Spiffy -base; use Clone qw(clone);   sub _print { my %self = %{shift()}; while (my ($k,$v) = each %self) { print "$k: $v\n"; } }   sub members { no strict; grep { 1 == length and defined *$_{CODE} } keys %{*{__PACKAGE__."\::"}}; }   sub new { my $class = shift; my %param = @_; $param{$_} = 0 for grep {!defined $param{$_}} members; bless \%param, $class; }   sub copy_constructor { clone shift; }   sub copy_assignment { my $self = shift; my $from = shift; $self->$_($from->$_) for $from->members; }   field 'x'; field 'y'; }   { package Circle; use base qw(Point); field 'r'; }   { package main; $_->_print, print "\n" for ( Point->new, Point->new(x => 2), Point->new(y => 3), Point->new(x => 8, y => -5), ); my $p1 = Point->new(x => 8, y => -5);   my $p2 = $p1->copy_constructor; print "we are really different objects, not just references ". "to the same instance\n" unless \$p1 eq \$p2;   # accessors autogenerated $p1->x(1); $p1->y(2); print $p1->x, "\n"; print $p1->y, "\n";   $p2->copy_assignment($p1); print $p2->x, "\n"; print $p2->y, "\n"; print "we now have the same values, but we are still ". "different objects\n" unless \$p1 eq \$p2;   $_->_print, print "\n" for ( Circle->new, Circle->new(x => 1), Circle->new(y => 2), Circle->new(r => 3), Circle->new(x => 4, y => 5), Circle->new(x => 6, r => 7), Circle->new(y => 8, r => 9), Circle->new(x => 1, y => 2, r => 3), );   my $c = Circle->new(r => 4); print $c->r, "\n"; # accessor autogenerated }
http://rosettacode.org/wiki/Population_count
Population count
Population count You are encouraged to solve this task according to the task description, using any language you may know. The   population count   is the number of   1s   (ones)   in the binary representation of a non-negative integer. Population count   is also known as:   pop count   popcount   sideways sum   bit summation   Hamming weight For example,   5   (which is   101   in binary)   has a population count of   2. Evil numbers   are non-negative integers that have an   even   population count. Odious numbers     are  positive integers that have an    odd   population count. Task write a function (or routine) to return the population count of a non-negative integer. all computation of the lists below should start with   0   (zero indexed). display the   pop count   of the   1st   thirty powers of   3       (30,   31,   32,   33,   34,   ∙∙∙   329). display the   1st   thirty     evil     numbers. display the   1st   thirty   odious   numbers. display each list of integers on one line   (which may or may not include a title),   each set of integers being shown should be properly identified. See also The On-Line Encyclopedia of Integer Sequences:   A000120 population count. The On-Line Encyclopedia of Integer Sequences:   A000069 odious numbers. The On-Line Encyclopedia of Integer Sequences:   A001969 evil numbers.
#JavaScript
JavaScript
(() => { 'use strict';   // populationCount :: Int -> Int const populationCount = n => // The number of non-zero bits in the binary // representation of the integer n. sum(unfoldr( x => 0 < x ? ( Just(Tuple(x % 2)(Math.floor(x / 2))) ) : Nothing() )(n));   // ----------------------- TEST ------------------------ // main :: IO () const main = () => { const [evens, odds] = Array.from( partition(compose(even, populationCount))( enumFromTo(0)(59) ) ); return [ 'Population counts of the first 30 powers of three:', ` [${enumFromTo(0)(29).map( compose(populationCount, raise(3)) ).join(',')}]`, "\nFirst thirty 'evil' numbers:", ` [${[evens.join(',')]}]`, "\nFirst thirty 'odious' numbers:", ` [${odds.join(',')}]` ].join('\n'); };     // ----------------- GENERIC FUNCTIONS -----------------   // Just :: a -> Maybe a const Just = x => ({ type: 'Maybe', Nothing: false, Just: x });     // Nothing :: Maybe a const Nothing = () => ({ type: 'Maybe', Nothing: true, });     // Tuple (,) :: a -> b -> (a, b) const Tuple = a => b => ({ type: 'Tuple', '0': a, '1': b, length: 2 });     // compose (<<<) :: (b -> c) -> (a -> b) -> a -> c const compose = (...fs) => // A function defined by the right-to-left // composition of all the functions in fs. fs.reduce( (f, g) => x => f(g(x)), x => x );     // enumFromTo :: Int -> Int -> [Int] const enumFromTo = m => n => !isNaN(m) ? ( Array.from({ length: 1 + n - m }, (_, i) => m + i) ) : enumFromTo_(m)(n);     // even :: Int -> Bool const even = n => // True if n is an even number. 0 === n % 2;     // partition :: (a -> Bool) -> [a] -> ([a], [a]) const partition = p => // A tuple of two lists - those elements in // xs which match p, and those which don't. xs => ([...xs]).reduce( (a, x) => p(x) ? ( Tuple(a[0].concat(x))(a[1]) ) : Tuple(a[0])(a[1].concat(x)), Tuple([])([]) );     // raise :: Num -> Int -> Num const raise = x => // X to the power of n. n => Math.pow(x, n);     // sum :: [Num] -> Num const sum = xs => // The numeric sum of all values in xs. xs.reduce((a, x) => a + x, 0);     // unfoldr :: (b -> Maybe (a, b)) -> b -> [a] const unfoldr = f => v => { const xs = []; let xr = [v, v]; while (true) { const mb = f(xr[1]); if (mb.Nothing) { return xs } else { xr = mb.Just; xs.push(xr[0]) } } };   // --- return main(); })();
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#Ursala
Ursala
#import std #import flo   polydiv =   zeroid~-l~~; leql?rlX\~&NlX ^H\(@rNrNSPXlHDlS |\ :/0.) @NlX //=> ?( @lrrPX ==!| zipp0.; @x not zeroid+ ==@h->hr ~&t, (^lryPX/~&lrrl2C minus^*p/~&rrr times*lrlPD)^/div@bzPrrPlXO ~&, @r ^|\~& ~&i&& :/0.)
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#VBA
VBA
Option Base 1 Function degree(p As Variant) For i = UBound(p) To 1 Step -1 If p(i) <> 0 Then degree = i Exit Function End If Next i degree = -1 End Function   Function poly_div(ByVal n As Variant, ByVal d As Variant) As Variant If UBound(d) < UBound(n) Then ReDim Preserve d(UBound(n)) End If Dim dn As Integer: dn = degree(n) Dim dd As Integer: dd = degree(d) If dd < 0 Then poly_div = CVErr(xlErrDiv0) Exit Function End If Dim quot() As Integer ReDim quot(dn) Do While dn >= dd Dim k As Integer: k = dn - dd Dim qk As Integer: qk = n(dn) / d(dd) quot(k + 1) = qk Dim d2() As Variant d2 = d ReDim Preserve d2(UBound(d) - k) For i = 1 To UBound(d2) n(UBound(n) + 1 - i) = n(UBound(n) + 1 - i) - d2(UBound(d2) + 1 - i) * qk Next i dn = degree(n) Loop poly_div = Array(quot, n) '-- (n is now the remainder) End Function   Function poly(si As Variant) As String '-- display helper Dim r As String For t = UBound(si) To 1 Step -1 Dim sit As Integer: sit = si(t) If sit <> 0 Then If sit = 1 And t > 1 Then r = r & IIf(r = "", "", " + ") Else If sit = -1 And t > 1 Then r = r & IIf(r = "", "-", " - ") Else If r <> "" Then r = r & IIf(sit < 0, " - ", " + ") sit = Abs(sit) End If r = r & CStr(sit) End If End If r = r & IIf(t > 1, "x" & IIf(t > 2, t - 1, ""), "") End If Next t If r = "" Then r = "0" poly = r End Function   Function polyn(s As Variant) As String Dim t() As String ReDim t(2 * UBound(s)) For i = 1 To 2 * UBound(s) Step 2 t(i) = poly(s((i + 1) / 2)) Next i t(1) = String$(45 - Len(t(1)) - Len(t(3)), " ") & t(1) t(2) = "/" t(4) = "=" t(6) = "rem" polyn = Join(t, " ") End Function   Public Sub main() Dim tests(7) As Variant tests(1) = Array(Array(-42, 0, -12, 1), Array(-3, 1)) tests(2) = Array(Array(-3, 1), Array(-42, 0, -12, 1)) tests(3) = Array(Array(-42, 0, -12, 1), Array(-3, 1, 1)) tests(4) = Array(Array(2, 3, 1), Array(1, 1)) tests(5) = Array(Array(3, 5, 6, -4, 1), Array(1, 2, 1)) tests(6) = Array(Array(3, 0, 7, 0, 0, 0, 0, 0, 3, 0, 0, 1), Array(1, 0, 0, 5, 0, 0, 0, 1)) tests(7) = Array(Array(-56, 87, -94, -55, 22, -7), Array(2, 0, 1)) Dim num As Variant, denom As Variant, quot As Variant, rmdr As Variant For i = 1 To 7 num = tests(i)(1) denom = tests(i)(2) tmp = poly_div(num, denom) quot = tmp(1) rmdr = tmp(2) Debug.Print polyn(Array(num, denom, quot, rmdr)) Next i End Sub
http://rosettacode.org/wiki/Polynomial_regression
Polynomial regression
Find an approximating polynomial of known degree for a given data. Example: For input data: x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}; The approximating polynomial is: 3 x2 + 2 x + 1 Here, the polynomial's coefficients are (3, 2, 1). This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Scala
Scala
object PolynomialRegression extends App { private def xy = Seq(1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321).zipWithIndex.map(_.swap)   private def polyRegression(xy: Seq[(Int, Int)]): Unit = { val r = xy.indices   def average[U](ts: Iterable[U])(implicit num: Numeric[U]) = num.toDouble(ts.sum) / ts.size   def x3m: Double = average(r.map(a => a * a * a)) def x4m: Double = average(r.map(a => a * a * a * a)) def x2ym = xy.reduce((a, x) => (a._1 + x._1 * x._1 * x._2, 0))._1.toDouble / xy.size def xym = xy.reduce((a, x) => (a._1 + x._1 * x._2, 0))._1.toDouble / xy.size   val x2m: Double = average(r.map(a => a * a)) val (xm, ym) = (average(xy.map(_._1)), average(xy.map(_._2))) val (sxx, sxy) = (x2m - xm * xm, xym - xm * ym) val sxx2: Double = x3m - xm * x2m val sx2x2: Double = x4m - x2m * x2m val sx2y: Double = x2ym - x2m * ym val c: Double = (sx2y * sxx - sxy * sxx2) / (sxx * sx2x2 - sxx2 * sxx2) val b: Double = (sxy * sx2x2 - sx2y * sxx2) / (sxx * sx2x2 - sxx2 * sxx2) val a: Double = ym - b * xm - c * x2m   def abc(xx: Int) = a + b * xx + c * xx * xx   println(s"y = $a + ${b}x + ${c}x^2") println(" Input Approximation") println(" x y y1") xy.foreach {el => println(f"${el._1}%2d ${el._2}%3d ${abc(el._1)}%5.1f")} }   polyRegression(xy)   }
http://rosettacode.org/wiki/Power_set
Power set
A   set   is a collection (container) of certain values, without any particular order, and no repeated values. It corresponds with a finite set in mathematics. A set can be implemented as an associative array (partial mapping) in which the value of each key-value pair is ignored. Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S. Task By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S. For example, the power set of     {1,2,3,4}     is {{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}. For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set. The power set of the empty set is the set which contains itself (20 = 1): P {\displaystyle {\mathcal {P}}} ( ∅ {\displaystyle \varnothing } ) = { ∅ {\displaystyle \varnothing } } And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2): P {\displaystyle {\mathcal {P}}} ({ ∅ {\displaystyle \varnothing } }) = { ∅ {\displaystyle \varnothing } , { ∅ {\displaystyle \varnothing } } } Extra credit: Demonstrate that your language supports these last two powersets.
#Logtalk
Logtalk
:- object(set).   :- public(powerset/2).   powerset(Set, PowerSet) :- reverse(Set, RSet), powerset_1(RSet, [[]], PowerSet).   powerset_1([], PowerSet, PowerSet). powerset_1([X| Xs], Yss0, Yss) :- powerset_2(Yss0, X, Yss1), powerset_1(Xs, Yss1, Yss).   powerset_2([], _, []). powerset_2([Zs| Zss], X, [Zs, [X| Zs]| Yss]) :- powerset_2(Zss, X, Yss).   reverse(List, Reversed) :- reverse(List, [], Reversed).   reverse([], Reversed, Reversed). reverse([Head| Tail], List, Reversed) :- reverse(Tail, [Head| List], Reversed).   :- end_object.
http://rosettacode.org/wiki/Primality_by_trial_division
Primality by trial division
Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops are allowed. Related tasks   count in factors   prime decomposition   AKS test for primes   factors of an integer   Sieve of Eratosthenes   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Factor
Factor
USING: combinators kernel math math.functions math.ranges sequences ;   : prime? ( n -- ? ) { { [ dup 2 < ] [ drop f ] } { [ dup even? ] [ 2 = ] } [ 3 over sqrt 2 <range> [ mod 0 > ] with all? ] } cond ;
http://rosettacode.org/wiki/Price_fraction
Price fraction
A friend of mine runs a pharmacy.   He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value.   This value is regulated by a government department. Task Given a floating point value between   0.00   and   1.00,   rescale according to the following table: >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00
#Pascal
Pascal
Program PriceFraction(output);   const limit: array [1..20] of real = (0.06, 0.11, 0.16, 0.21, 0.26, 0.31, 0.36, 0.41, 0.46, 0.51, 0.56, 0.61, 0.66, 0.71, 0.76, 0.81, 0.86, 0.91, 0.96, 1.01); price: array [1..20] of real = (0.10, 0.18, 0.26, 0.32, 0.38, 0.44, 0.50, 0.54, 0.58, 0.62, 0.66, 0.70, 0.74, 0.78, 0.81, 0.86, 0.90, 0.94, 0.98, 1.00);   var cost: real; i, j: integer;   begin randomize; for i := 1 to 10 do begin cost := random; j := high(limit); while cost < limit[j] do dec(j); writeln (cost:6:4, ' -> ', price[j+1]:4:2); end; end.
http://rosettacode.org/wiki/Proper_divisors
Proper divisors
The   proper divisors   of a positive integer N are those numbers, other than N itself, that divide N without remainder. For N > 1 they will always include 1,   but for N == 1 there are no proper divisors. Examples The proper divisors of     6     are   1, 2, and 3. The proper divisors of   100   are   1, 2, 4, 5, 10, 20, 25, and 50. Task Create a routine to generate all the proper divisors of a number. use it to show the proper divisors of the numbers 1 to 10 inclusive. Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has. Show all output here. Related tasks   Amicable pairs   Abundant, deficient and perfect number classifications   Aliquot sequence classifications   Factors of an integer   Prime decomposition
#R
R
# Proper divisors. 12/10/16 aev require(numbers); V <- sapply(1:20000, Sigma, k = 0, proper = TRUE); ind <- which(V==max(V)); cat(" *** max number of divisors:", max(V), "\n"," *** for the following indices:",ind, "\n");
http://rosettacode.org/wiki/Priority_queue
Priority queue
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order. Task Create a priority queue.   The queue must support at least two operations:   Insertion.   An element is added to the queue with a priority (a numeric value).   Top item removal.   Deletes the element or one of the elements with the current top priority and return it. Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc. To test your implementation, insert a number of elements into the queue, each with some random priority. Then dequeue them sequentially; now the elements should be sorted by priority. You can use the following task/priority items as input data: Priority Task ══════════ ════════════════ 3 Clear drains 4 Feed cat 5 Make tea 1 Solve RC tasks 2 Tax return The implementation should try to be efficient.   A typical implementation has   O(log n)   insertion and extraction time,   where   n   is the number of items in the queue. You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc.   If so, discuss the reasons behind it.
#SAS
SAS
%macro HeapInit(size=1000,nchar=20); do; _len = 0; _size = &size; array _times(&size) _temporary_ ; array _kinds(&size) $ &nchar _temporary_; drop _size _len; end; %mend; %macro HeapSwapItem(index1, index2); do; _tempN = _times[&index1]; _times[&index1] = _times[&index2]; _times[&index2] = _tempN; _tempC = _kinds[&index1]; _kinds[&index1] = _kinds[&index2]; _kinds[&index2]= _tempC; drop _tempN _tempC; end; %mend; %macro HeapEmpty; (_len=0) %mend; %macro HeapCompare(index1, index2); (_times[&index1] < _times[&index2]) %mend; %macro HeapSiftdown(index); do; _parent = &index; _done = 0; do while (_parent*2 <= _len & ^_done); _child = _parent*2; if (_child+1 <= _len and %HeapCompare(_child+1,_child)) then _child = _child + 1; if %HeapCompare(_child,_parent) then do; %HeapSwapItem(_child,_parent); _parent = _child; end; else _done = 1; end; drop _done _parent _child; end; %mend; %macro HeapSiftup(index); do; _child = &index; _done = 0; do while(_child>1 and ^_done); _parent = floor(_child/2); if %HeapCompare(_parent,_child) then _done = 1; else do; %HeapSwapItem(_child,_parent); _tempN = _child; _child = _parent; _parent = _tempN; end; end; drop _parent _child _done _tempN; end; %mend; %macro HeapPush(time, kind); do; if _len >= _size then do; put "ERROR: exceeded size of heap. Consider changing size argument to %HeapInit."; stop; end; _len = _len + 1; _times[_len] = &time; _kinds[_len] = &kind; %HeapSiftup(_len); end; %mend; %macro HeapPop; do; _len = _len - 1; if (_len>0) then do; _times[1] = _times[_len+1]; _kinds[1] = _kinds[_len+1]; %HeapSiftdown(1); end; end; %mend; %macro HeapPeek; time = _times[1]; kind = _kinds[1]; put time kind; %mend; data _null_; %HeapInit; %HeapPush(3, "Clear drains"); %HeapPush(4, "Feed cat"); %HeapPush(5, "Make tea"); %HeapPush(1, "Solve RC tasks"); %HeapPush(2, "Tax return"); do while(^%HeapEmpty); %HeapPeek; %HeapPop; end; run;
http://rosettacode.org/wiki/Prime_decomposition
Prime decomposition
The prime decomposition of a number is defined as a list of prime numbers which when all multiplied together, are equal to that number. Example 12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3} Task Write a function which returns an array or collection which contains the prime decomposition of a given number   n {\displaystyle n}   greater than   1. If your language does not have an isPrime-like function available, you may assume that you have a function which determines whether a number is prime (note its name before your code). If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes. Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc). Related tasks   count in factors   factors of an integer   Sieve of Eratosthenes   primality by trial division   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Logo
Logo
to decompose :n [:p 2] if :p*:p > :n [output (list :n)] if less? 0 modulo :n :p [output (decompose :n bitor 1 :p+1)] output fput :p (decompose :n/:p :p) end
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#R
R
x <- c(0, 1, 2, 3, 4, 5, 6, 7, 8, 9) y <- c(2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0)
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Racket
Racket
#lang racket (require plot)   (define x (build-list 10 values)) (define y (list 2.7 2.8 31.4 38.1 58.0 76.2 100.5 130.0 149.3 180.0))   (plot-new-window? #t) (plot (points (map vector x y)))
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#Phix
Phix
type point(object o) return sequence(o) and length(o)=2 and atom(o[1]) and atom(o[2]) end type function new_point(atom x=0, atom y=0) return {x,y} end function type circle(object o) return sequence(o) and length(o)=2 and point(o[1]) and atom(o[2]) end type function new_circle(object x=0, atom y=0, atom r=0) if point(x) then r = y -- assume r got passed in y return {x,r} -- {point,r} end if return {{x,y},r} -- {point,r} -- (or {new_point(x,y),r} if you prefer) end function point p = new_point(4,5) circle c1 = new_circle(p,6), c2 = new_circle(4,5,6} ?c1 ?c2
http://rosettacode.org/wiki/Population_count
Population count
Population count You are encouraged to solve this task according to the task description, using any language you may know. The   population count   is the number of   1s   (ones)   in the binary representation of a non-negative integer. Population count   is also known as:   pop count   popcount   sideways sum   bit summation   Hamming weight For example,   5   (which is   101   in binary)   has a population count of   2. Evil numbers   are non-negative integers that have an   even   population count. Odious numbers     are  positive integers that have an    odd   population count. Task write a function (or routine) to return the population count of a non-negative integer. all computation of the lists below should start with   0   (zero indexed). display the   pop count   of the   1st   thirty powers of   3       (30,   31,   32,   33,   34,   ∙∙∙   329). display the   1st   thirty     evil     numbers. display the   1st   thirty   odious   numbers. display each list of integers on one line   (which may or may not include a title),   each set of integers being shown should be properly identified. See also The On-Line Encyclopedia of Integer Sequences:   A000120 population count. The On-Line Encyclopedia of Integer Sequences:   A000069 odious numbers. The On-Line Encyclopedia of Integer Sequences:   A001969 evil numbers.
#jq
jq
def popcount: def bin: recurse( if . == 0 then empty else ./2 | floor end ) % 2; [bin] | add;   def firstN(count; condition): if count > 0 then if condition then ., (1+.| firstN(count-1; condition)) else (1+.) | firstN(count; condition) end else empty end;   def task: def pow(n): . as $m | reduce range(0;n) as $i (1; . * $m);   "The pop count of the first thirty powers of 3:", [range(0;30) as $n | 3 | pow($n) | popcount],   "The first thirty evil numbers:", [0 | firstN(30; (popcount % 2) == 0)],   "The first thirty odious numbers:", [0 | firstN(30; (popcount % 2) == 1)] ;   task
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#Wren
Wren
import "/dynamic" for Tuple   var Solution = Tuple.create("Solution", ["quotient", "remainder"])   var polyDegree = Fn.new { |p| for (i in p.count-1..0) if (p[i] != 0) return i return -2.pow(31) }   var polyShiftRight = Fn.new { |p, places| if (places <= 0) return p var pd = polyDegree.call(p) if (pd + places >= p.count) { Fiber.abort("The number of places to be shifted is too large.") } var d = p.toList for (i in pd..0) { d[i + places] = d[i] d[i] = 0 } return d }   var polyMultiply = Fn.new { |p, m| for (i in 0...p.count) p[i] = p[i] * m }   var polySubtract = Fn.new { |p, s| for (i in 0...p.count) p[i] = p[i] - s[i] }   var polyLongDiv = Fn.new { |n, d| if (n.count != d.count) { Fiber.abort("Numerator and denominator vectors must have the same size") } var nd = polyDegree.call(n) var dd = polyDegree.call(d) if (dd < 0) { Fiber.abort("Divisor must have at least one one-zero coefficient") } if (nd < dd) { Fiber.abort("The degree of the divisor cannot exceed that of the numerator") } var n2 = n.toList var q = List.filled(n.count, 0) while (nd >= dd) { var d2 = polyShiftRight.call(d, nd - dd) q[nd - dd] = n2[nd] / d2[nd] polyMultiply.call(d2, q[nd - dd]) polySubtract.call(n2, d2) nd = polyDegree.call(n2) } return Solution.new(q, n2) }   var polyShow = Fn.new { |p| var pd = polyDegree.call(p) for (i in pd..0) { var coeff = p[i] if (coeff != 0) { System.write( (coeff == 1) ? ((i < pd) ? " + " : "") : (coeff == -1) ? ((i < pd) ? " - " : "-") : (coeff < 0) ? ((i < pd) ? " - %(-coeff)" : "%(coeff)") : ((i < pd) ? " + %( coeff)" : "%(coeff)") ) if (i > 1) { System.write("x^%(i)") } else if (i == 1) { System.write("x") } } } System.print() }   var n = [-42, 0, -12, 1] var d = [ -3, 1, 0, 0] System.write("Numerator  : ") polyShow.call(n) System.write("Denominator : ") polyShow.call(d) System.print("-------------------------------------") var sol = polyLongDiv.call(n, d) System.write("Quotient  : ") polyShow.call(sol.quotient) System.write("Remainder  : ") polyShow.call(sol.remainder)
http://rosettacode.org/wiki/Polynomial_regression
Polynomial regression
Find an approximating polynomial of known degree for a given data. Example: For input data: x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}; The approximating polynomial is: 3 x2 + 2 x + 1 Here, the polynomial's coefficients are (3, 2, 1). This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Sidef
Sidef
func regress(x, y, degree) { var A = Matrix.build(x.len, degree+1, {|i,j| x[i]**j })   var B = Matrix.column_vector(y...) ((A.transpose * A)**(-1) * A.transpose * B).transpose[0] }   func poly(x) { 3*x**2 + 2*x + 1 }   var coeff = regress( 10.of { _ }, 10.of { poly(_) }, 2 )   say coeff
http://rosettacode.org/wiki/Power_set
Power set
A   set   is a collection (container) of certain values, without any particular order, and no repeated values. It corresponds with a finite set in mathematics. A set can be implemented as an associative array (partial mapping) in which the value of each key-value pair is ignored. Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S. Task By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S. For example, the power set of     {1,2,3,4}     is {{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}. For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set. The power set of the empty set is the set which contains itself (20 = 1): P {\displaystyle {\mathcal {P}}} ( ∅ {\displaystyle \varnothing } ) = { ∅ {\displaystyle \varnothing } } And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2): P {\displaystyle {\mathcal {P}}} ({ ∅ {\displaystyle \varnothing } }) = { ∅ {\displaystyle \varnothing } , { ∅ {\displaystyle \varnothing } } } Extra credit: Demonstrate that your language supports these last two powersets.
#Lua
Lua
  --returns the powerset of s, out of order. function powerset(s, start) start = start or 1 if(start > #s) then return {{}} end local ret = powerset(s, start + 1) for i = 1, #ret do ret[#ret + 1] = {s[start], unpack(ret[i])} end return ret end   --non-recurse implementation function powerset(s) local t = {{}} for i = 1, #s do for j = 1, #t do t[#t+1] = {s[i],unpack(t[j])} end end return t end   --alternative, copied from the Python implementation function powerset2(s) local ret = {{}} for i = 1, #s do local k = #ret for j = 1, k do ret[k + j] = {s[i], unpack(ret[j])} end end return ret end  
http://rosettacode.org/wiki/Primality_by_trial_division
Primality by trial division
Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops are allowed. Related tasks   count in factors   prime decomposition   AKS test for primes   factors of an integer   Sieve of Eratosthenes   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#FALSE
FALSE
[0\$2=$[@~@@]?~[$$2>\1&&[\~\ 3[\$@$@1+\$*>][\$@$@$@$@\/*=[%\~\$]?2+]#% ]?]?%]p:
http://rosettacode.org/wiki/Price_fraction
Price fraction
A friend of mine runs a pharmacy.   He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value.   This value is regulated by a government department. Task Given a floating point value between   0.00   and   1.00,   rescale according to the following table: >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00
#Perl
Perl
my @table = map [ /([\d\.]+)/g ], split "\n", <<'TBL'; >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00 TBL   sub convert { my $money = shift; for (@table) { return $_->[2] if $_->[0] <= $money and $_->[1] > $money } die "Can't find currency conversion for $money. Counterfeit?" }   # try it out for (1 .. 10) { my $m = rand(1); printf "%.3f -> %g\n", $m, convert($m); }  
http://rosettacode.org/wiki/Proper_divisors
Proper divisors
The   proper divisors   of a positive integer N are those numbers, other than N itself, that divide N without remainder. For N > 1 they will always include 1,   but for N == 1 there are no proper divisors. Examples The proper divisors of     6     are   1, 2, and 3. The proper divisors of   100   are   1, 2, 4, 5, 10, 20, 25, and 50. Task Create a routine to generate all the proper divisors of a number. use it to show the proper divisors of the numbers 1 to 10 inclusive. Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has. Show all output here. Related tasks   Amicable pairs   Abundant, deficient and perfect number classifications   Aliquot sequence classifications   Factors of an integer   Prime decomposition
#Racket
Racket
#lang racket (require math) (define (proper-divisors n) (drop-right (divisors n) 1)) (for ([n (in-range 1 (add1 10))]) (printf "proper divisors of: ~a\t~a\n" n (proper-divisors n))) (define most-under-20000 (for/fold ([best '(1)]) ([n (in-range 2 (add1 20000))]) (define divs (proper-divisors n)) (if (< (length (cdr best)) (length divs)) (cons n divs) best))) (printf "~a has ~a proper divisors\n" (car most-under-20000) (length (cdr most-under-20000)))
http://rosettacode.org/wiki/Priority_queue
Priority queue
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order. Task Create a priority queue.   The queue must support at least two operations:   Insertion.   An element is added to the queue with a priority (a numeric value).   Top item removal.   Deletes the element or one of the elements with the current top priority and return it. Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc. To test your implementation, insert a number of elements into the queue, each with some random priority. Then dequeue them sequentially; now the elements should be sorted by priority. You can use the following task/priority items as input data: Priority Task ══════════ ════════════════ 3 Clear drains 4 Feed cat 5 Make tea 1 Solve RC tasks 2 Tax return The implementation should try to be efficient.   A typical implementation has   O(log n)   insertion and extraction time,   where   n   is the number of items in the queue. You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc.   If so, discuss the reasons behind it.
#Scala
Scala
import scala.collection.mutable.PriorityQueue case class Task(prio:Int, text:String) extends Ordered[Task] { def compare(that: Task)=that.prio compare this.prio }   //test var q=PriorityQueue[Task]() ++ Seq(Task(3, "Clear drains"), Task(4, "Feed cat"), Task(5, "Make tea"), Task(1, "Solve RC tasks"), Task(2, "Tax return")) while(q.nonEmpty) println(q dequeue)
http://rosettacode.org/wiki/Prime_decomposition
Prime decomposition
The prime decomposition of a number is defined as a list of prime numbers which when all multiplied together, are equal to that number. Example 12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3} Task Write a function which returns an array or collection which contains the prime decomposition of a given number   n {\displaystyle n}   greater than   1. If your language does not have an isPrime-like function available, you may assume that you have a function which determines whether a number is prime (note its name before your code). If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes. Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc). Related tasks   count in factors   factors of an integer   Sieve of Eratosthenes   primality by trial division   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#Lua
Lua
function PrimeDecomposition( n ) local f = {}   if IsPrime( n ) then f[1] = n return f end   local i = 2 repeat while n % i == 0 do f[#f+1] = i n = n / i end   repeat i = i + 1 until IsPrime( i ) until n == 1   return f end
http://rosettacode.org/wiki/Plot_coordinate_pairs
Plot coordinate pairs
Task Plot a function represented as    x,  y    numerical arrays. Post the resulting image for the following input arrays (taken from Python's Example section on Time a function): x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0}; This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Raku
Raku
use SVG; use SVG::Plot;   my @x = 0..9; my @y = (2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0);   say SVG.serialize: SVG::Plot.new( width => 512, height => 512, x => @x, x-tick-step => { 1 }, min-y-axis => 0, values => [@y,], title => 'Coordinate Pairs', ).plot(:lines);
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#PHP
PHP
  class Point { protected $_x;   protected $_y;   public function __construct() { switch( func_num_args() ) { case 1: $point = func_get_arg( 0 ); $this->setFromPoint( $point ); break; case 2: $x = func_get_arg( 0 ); $y = func_get_arg( 1 ); $this->setX( $x ); $this->setY( $y ); break; default: throw new InvalidArgumentException( 'expecting one (Point) argument or two (numeric x and y) arguments' ); } }   public function setFromPoint( Point $point ) { $this->setX( $point->getX() ); $this->setY( $point->getY() ); }   public function getX() { return $this->_x; }   public function setX( $x ) { if( !is_numeric( $x ) ) { throw new InvalidArgumentException( 'expecting numeric value' ); }   $this->_x = (float) $x; }   public function getY() { return $this->_y; }   public function setY( $y ) { if( !is_numeric( $y ) ) { throw new InvalidArgumentException( 'expecting numeric value' ); }   $this->_y = (float) $y; }   public function output() { echo $this->__toString(); }   public function __toString() { return 'Point [x:' . $this->_x . ',y:' . $this->_y . ']'; } }  
http://rosettacode.org/wiki/Population_count
Population count
Population count You are encouraged to solve this task according to the task description, using any language you may know. The   population count   is the number of   1s   (ones)   in the binary representation of a non-negative integer. Population count   is also known as:   pop count   popcount   sideways sum   bit summation   Hamming weight For example,   5   (which is   101   in binary)   has a population count of   2. Evil numbers   are non-negative integers that have an   even   population count. Odious numbers     are  positive integers that have an    odd   population count. Task write a function (or routine) to return the population count of a non-negative integer. all computation of the lists below should start with   0   (zero indexed). display the   pop count   of the   1st   thirty powers of   3       (30,   31,   32,   33,   34,   ∙∙∙   329). display the   1st   thirty     evil     numbers. display the   1st   thirty   odious   numbers. display each list of integers on one line   (which may or may not include a title),   each set of integers being shown should be properly identified. See also The On-Line Encyclopedia of Integer Sequences:   A000120 population count. The On-Line Encyclopedia of Integer Sequences:   A000069 odious numbers. The On-Line Encyclopedia of Integer Sequences:   A001969 evil numbers.
#Julia
Julia
println("First 3 ^ i, up to 29 pop. counts: ", join((count_ones(3 ^ n) for n in 0:29), ", ")) println("Evil numbers: ", join(filter(x -> iseven(count_ones(x)), 0:59), ", ")) println("Odious numbers: ", join(filter(x -> isodd(count_ones(x)), 0:59), ", "))
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In algebra, polynomial long division is an algorithm for dividing a polynomial by another polynomial of the same or lower degree. Let us suppose a polynomial is represented by a vector, x {\displaystyle x} (i.e., an ordered collection of coefficients) so that the i {\displaystyle i} th element keeps the coefficient of x i {\displaystyle x^{i}} , and the multiplication by a monomial is a shift of the vector's elements "towards right" (injecting ones from left) followed by a multiplication of each element by the coefficient of the monomial. Then a pseudocode for the polynomial long division using the conventions described above could be: degree(P): return the index of the last non-zero element of P; if all elements are 0, return -∞ polynomial_long_division(N, D) returns (q, r): // N, D, q, r are vectors if degree(D) < 0 then error q ← 0 while degree(N) ≥ degree(D) d ← D shifted right by (degree(N) - degree(D)) q(degree(N) - degree(D)) ← N(degree(N)) / d(degree(d)) // by construction, degree(d) = degree(N) of course d ← d * q(degree(N) - degree(D)) N ← N - d endwhile r ← N return (q, r) Note: vector * scalar multiplies each element of the vector by the scalar; vectorA - vectorB subtracts each element of the vectorB from the element of the vectorA with "the same index". The vectors in the pseudocode are zero-based. Error handling (for allocations or for wrong inputs) is not mandatory. Conventions can be different; in particular, note that if the first coefficient in the vector is the highest power of x for the polynomial represented by the vector, then the algorithm becomes simpler. Example for clarification This example is from Wikipedia, but changed to show how the given pseudocode works. 0 1 2 3 ---------------------- N: -42 0 -12 1 degree = 3 D: -3 1 0 0 degree = 1 d(N) - d(D) = 2, so let's shift D towards right by 2: N: -42 0 -12 1 d: 0 0 -3 1 N(3)/d(3) = 1, so d is unchanged. Now remember that "shifting by 2" is like multiplying by x2, and the final multiplication (here by 1) is the coefficient of this monomial. Let's store this into q: 0 1 2 --------------- q: 0 0 1 now compute N - d, and let it be the "new" N, and let's loop N: -42 0 -9 0 degree = 2 D: -3 1 0 0 degree = 1 d(N) - d(D) = 1, right shift D by 1 and let it be d N: -42 0 -9 0 d: 0 -3 1 0 * -9/1 = -9 q: 0 -9 1 d: 0 27 -9 0 N ← N - d N: -42 -27 0 0 degree = 1 D: -3 1 0 0 degree = 1 looping again... d(N)-d(D)=0, so no shift is needed; we multiply D by -27 (= -27/1) storing the result in d, then q: -27 -9 1 and N: -42 -27 0 0 - d: 81 -27 0 0 = N: -123 0 0 0 (last N) d(N) < d(D), so now r ← N, and the result is: 0 1 2 ------------- q: -27 -9 1 → x2 - 9x - 27 r: -123 0 0 → -123 Related task   Polynomial derivative
#zkl
zkl
fcn polyLongDivision(a,b){ // (a0 + a1x + a2x^2 + a3x^3 ...) _assert_(degree(b)>=0,"degree(%s) < 0".fmt(b)); q:=List.createLong(a.len(),0.0); while((ad:=degree(a)) >= (bd:=degree(b))){ z,d,m := ad-bd, List.createLong(z,0.0).extend(b), a[ad]/b[bd];; q[z]=m; d,a = d.apply('*(m)), a.zipWith('-,d); } return(q,a); // may have trailing zero elements } fcn degree(v){ // -1,0,..len(v)-1, -1 if v==0 v.len() - v.copy().reverse().filter1n('!=(0)) - 1; } fcn polyString(terms){ // (a0,a1,a2...)-->"a0 + a1x + a2x^2 ..." str:=[0..].zipWith('wrap(n,a){ if(a) "+ %sx^%s ".fmt(a,n) else "" },terms) .pump(String) .replace("x^0 "," ").replace(" 1x"," x").replace("x^1 ","x ") .replace("+ -", "- "); if(not str) return(" "); // all zeros if(str[0]=="+") str[1,*]; // leave leading space else String("-",str[2,*]); }
http://rosettacode.org/wiki/Polynomial_regression
Polynomial regression
Find an approximating polynomial of known degree for a given data. Example: For input data: x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}; The approximating polynomial is: 3 x2 + 2 x + 1 Here, the polynomial's coefficients are (3, 2, 1). This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Stata
Stata
. clear . input x y 0 1 1 6 2 17 3 34 4 57 5 86 6 121 7 162 8 209 9 262 10 321 end   . regress y c.x##c.x   Source | SS df MS Number of obs = 11 -------------+---------------------------------- F(2, 8) = . Model | 120362 2 60181 Prob > F = . Residual | 0 8 0 R-squared = 1.0000 -------------+---------------------------------- Adj R-squared = 1.0000 Total | 120362 10 12036.2 Root MSE = 0   ------------------------------------------------------------------------------ y | Coef. Std. Err. t P>|t| [95% Conf. Interval] -------------+---------------------------------------------------------------- x | 2 . . . . . | c.x#c.x | 3 . . . . . | _cons | 1 . . . . . ------------------------------------------------------------------------------
http://rosettacode.org/wiki/Power_set
Power set
A   set   is a collection (container) of certain values, without any particular order, and no repeated values. It corresponds with a finite set in mathematics. A set can be implemented as an associative array (partial mapping) in which the value of each key-value pair is ignored. Given a set S, the power set (or powerset) of S, written P(S), or 2S, is the set of all subsets of S. Task By using a library or built-in set type, or by defining a set type with necessary operations, write a function with a set S as input that yields the power set 2S of S. For example, the power set of     {1,2,3,4}     is {{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}. For a set which contains n elements, the corresponding power set has 2n elements, including the edge cases of empty set. The power set of the empty set is the set which contains itself (20 = 1): P {\displaystyle {\mathcal {P}}} ( ∅ {\displaystyle \varnothing } ) = { ∅ {\displaystyle \varnothing } } And the power set of the set which contains only the empty set, has two subsets, the empty set and the set which contains the empty set (21 = 2): P {\displaystyle {\mathcal {P}}} ({ ∅ {\displaystyle \varnothing } }) = { ∅ {\displaystyle \varnothing } , { ∅ {\displaystyle \varnothing } } } Extra credit: Demonstrate that your language supports these last two powersets.
#M4
M4
define(`for', `ifelse($#, 0, ``$0'', eval($2 <= $3), 1, `pushdef(`$1', `$2')$4`'popdef( `$1')$0(`$1', incr($2), $3, `$4')')')dnl define(`nth', `ifelse($1, 1, $2, `nth(decr($1), shift(shift($@)))')')dnl define(`range', `for(`x', eval($1 + 2), eval($2 + 2), `nth(x, $@)`'ifelse(x, eval($2+2), `', `,')')')dnl define(`powerpart', `{range(2, incr($1), $@)}`'ifelse(incr($1), $#, `', `for(`x', eval($1+2), $#, `,powerpart(incr($1), ifelse( eval(2 <= ($1 + 1)), 1, `range(2,incr($1), $@), ')`'nth(x, $@)`'ifelse( eval((x + 1) <= $#),1,`,range(incr(x), $#, $@)'))')')')dnl define(`powerset', `{powerpart(0, substr(`$1', 1, eval(len(`$1') - 2)))}')dnl dnl powerset(`{a,b,c}')
http://rosettacode.org/wiki/Primality_by_trial_division
Primality by trial division
Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops are allowed. Related tasks   count in factors   prime decomposition   AKS test for primes   factors of an integer   Sieve of Eratosthenes   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#FBSL
FBSL
#APPTYPE CONSOLE   FUNCTION ISPRIME(n AS INTEGER) AS INTEGER IF n = 2 THEN RETURN TRUE ELSEIF n <= 1 ORELSE n MOD 2 = 0 THEN RETURN FALSE ELSE FOR DIM i = 3 TO SQR(n) STEP 2 IF n MOD i = 0 THEN RETURN FALSE END IF NEXT RETURN TRUE END IF END FUNCTION   FUNCTION ISPRIME2(N AS INTEGER) AS INTEGER IF N <= 1 THEN RETURN FALSE DIM I AS INTEGER = 2 WHILE I * I <= N IF N MOD I = 0 THEN RETURN FALSE END IF I = I + 1 WEND RETURN TRUE END FUNCTION   ' Test and display primes 1 .. 50 DIM n AS INTEGER   FOR n = 1 TO 50 IF ISPRIME(n) THEN PRINT n, " "; END IF NEXT   PAUSE
http://rosettacode.org/wiki/Price_fraction
Price fraction
A friend of mine runs a pharmacy.   He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value.   This value is regulated by a government department. Task Given a floating point value between   0.00   and   1.00,   rescale according to the following table: >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00
#Phix
Phix
with javascript_semantics constant TBL=split(""" >= 0.00 < 0.06  := 0.10 >= 0.06 < 0.11  := 0.18 >= 0.11 < 0.16  := 0.26 >= 0.16 < 0.21  := 0.32 >= 0.21 < 0.26  := 0.38 >= 0.26 < 0.31  := 0.44 >= 0.31 < 0.36  := 0.50 >= 0.36 < 0.41  := 0.54 >= 0.41 < 0.46  := 0.58 >= 0.46 < 0.51  := 0.62 >= 0.51 < 0.56  := 0.66 >= 0.56 < 0.61  := 0.70 >= 0.61 < 0.66  := 0.74 >= 0.66 < 0.71  := 0.78 >= 0.71 < 0.76  := 0.82 >= 0.76 < 0.81  := 0.86 >= 0.81 < 0.86  := 0.90 >= 0.86 < 0.91  := 0.94 >= 0.91 < 0.96  := 0.98 >= 0.96 < 1.01  := 1.00""",'\n') sequence limits = {0}, prices = {-1} atom pl,lt,plt=0,price for i=1 to length(TBL) do {pl,lt,price} = scanf(TBL[i],">=  %.2f <  %.2f  :=  %.2f")[1] assert(pl==plt) plt = lt limits = append(limits,lt) prices = append(prices,price) end for function price_fix(atom p) for i=1 to length(limits) do if p<limits[i] then return prices[i] end if end for return -1 end function for i=-1 to 101 do printf(1, "%5.2f %5.2f\n", {i/100,price_fix(i/100)}) end for
http://rosettacode.org/wiki/Proper_divisors
Proper divisors
The   proper divisors   of a positive integer N are those numbers, other than N itself, that divide N without remainder. For N > 1 they will always include 1,   but for N == 1 there are no proper divisors. Examples The proper divisors of     6     are   1, 2, and 3. The proper divisors of   100   are   1, 2, 4, 5, 10, 20, 25, and 50. Task Create a routine to generate all the proper divisors of a number. use it to show the proper divisors of the numbers 1 to 10 inclusive. Find a number in the range 1 to 20,000 with the most proper divisors. Show the number and just the count of how many proper divisors it has. Show all output here. Related tasks   Amicable pairs   Abundant, deficient and perfect number classifications   Aliquot sequence classifications   Factors of an integer   Prime decomposition
#Raku
Raku
sub propdiv (\x) { my @l = 1 if x > 1; (2 .. x.sqrt.floor).map: -> \d { unless x % d { @l.push: d; my \y = x div d; @l.push: y if y != d } } @l }   put "$_ [{propdiv($_)}]" for 1..10;   my @candidates; loop (my int $c = 30; $c <= 20_000; $c += 30) { #(30, *+30 …^ * > 500_000).race.map: -> $c { my \mx = +propdiv($c); next if mx < @candidates - 1; @candidates[mx].push: $c }   say "max = {@candidates - 1}, candidates = {@candidates.tail}";
http://rosettacode.org/wiki/Priority_queue
Priority queue
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insertion order. Task Create a priority queue.   The queue must support at least two operations:   Insertion.   An element is added to the queue with a priority (a numeric value).   Top item removal.   Deletes the element or one of the elements with the current top priority and return it. Optionally, other operations may be defined, such as peeking (find what current top priority/top element is), merging (combining two priority queues into one), etc. To test your implementation, insert a number of elements into the queue, each with some random priority. Then dequeue them sequentially; now the elements should be sorted by priority. You can use the following task/priority items as input data: Priority Task ══════════ ════════════════ 3 Clear drains 4 Feed cat 5 Make tea 1 Solve RC tasks 2 Tax return The implementation should try to be efficient.   A typical implementation has   O(log n)   insertion and extraction time,   where   n   is the number of items in the queue. You may choose to impose certain limits such as small range of allowed priority levels, limited capacity, etc.   If so, discuss the reasons behind it.
#SenseTalk
SenseTalk
  // PriorityQueue.script set Tasks to a new PriorityQueue   tell Tasks to add 3,"Clear drains" tell Tasks to add 4,"Feed cat" tell Tasks to add 5,"Make tea" tell Tasks to add 1,"Solve RC tasks" tell Tasks to add 2,"Tax return"   put "Initial tasks:" put Tasks.report & return   put Tasks.getTop into topItem put "Top priority: " & topItem & return   put "Remaining:" & return & Tasks.report   ------ properties queue:[] end properties   to add newPriority, newTask repeat with each item of my queue if newPriority comes before the priority of it then insert {priority:newPriority, task:newTask} before item the counter of my queue return end if end repeat insert {priority:newPriority, task:newTask} into my queue -- add at end if last priority end add   to getTop pull my queue into firstItem return firstItem end getTop   to report return (priority of each && task of each for each item of my queue) joined by return end report  
http://rosettacode.org/wiki/Prime_decomposition
Prime decomposition
The prime decomposition of a number is defined as a list of prime numbers which when all multiplied together, are equal to that number. Example 12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3} Task Write a function which returns an array or collection which contains the prime decomposition of a given number   n {\displaystyle n}   greater than   1. If your language does not have an isPrime-like function available, you may assume that you have a function which determines whether a number is prime (note its name before your code). If you would like to test code from this task, you may use code from trial division or the Sieve of Eratosthenes. Note: The program must not be limited by the word size of your computer or some other artificial limit; it should work for any number regardless of size (ignoring the physical limits of RAM etc). Related tasks   count in factors   factors of an integer   Sieve of Eratosthenes   primality by trial division   factors of a Mersenne number   trial factoring of a Mersenne number   partition an integer X into N primes   sequence of primes by Trial Division
#M2000_Interpreter
M2000 Interpreter
  Module Prime_decomposition { Inventory Known1=2@, 3@ IsPrime=lambda Known1 (x as decimal) -> { =0=1 if exist(Known1, x) then =1=1 : exit if x<=5 OR frac(x) then {if x == 2 OR x == 3 OR x == 5 then Append Known1, x  : =1=1 Break} if frac(x/2) else exit if frac(x/3) else exit x1=sqrt(x):d = 5@ {if frac(x/d ) else exit d += 2: if d>x1 then Append Known1, x : =1=1 : exit if frac(x/d) else exit d += 4: if d<= x1 else Append Known1, x : =1=1: exit loop} } decompose=lambda IsPrime (n as decimal) -> { Inventory queue Factors { k=2@ While frac(n/k)=0 { n/=k Append Factors, k } if n=1 then exit k++ While frac(n/k)=0 { n/=k Append Factors, k } if n=1 then exit { k+=2 while not isprime(k) {k+=2} While frac(n/k)=0 { n/=k Append Factors, k } if n=1 then exit loop } } =Factors } Data 10, 100, 12, 144, 496, 1212454 while not empty { Print Decompose(Number) } } Prime_decomposition