task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k |
|---|---|---|---|---|---|
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #Stata | Stata | * Read rows 20 to 30 from somedata.dta
. use somedata in 20/30, clear
* Read rows for which the variable x is positive
. use somedata if x>0, clear |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #Tcl | Tcl | proc getNthLineFromFile {filename n} {
set f [open $filename]
while {[incr n -1] > 0} {
if {[gets $f line] < 0} {
close $f
error "no such line"
}
}
close $f
return $line
}
puts [getNthLineFromFile example.txt 7] |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Delphi | Delphi |
program Quickselect_algorithm;
{$APPTYPE CONSOLE}
uses
System.SysUtils;
function quickselect(list: TArray<Integer>; k: Integer): Integer;
procedure Swap(i, j: Integer);
var
tmp: Integer;
begin
tmp := list[i];
list[i] := list[j];
list[j] := tmp;
end;
begin
repeat
var px := len... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #Rust | Rust | #[derive(Copy, Clone)]
struct Point {
x: f64,
y: f64,
}
use std::fmt;
impl fmt::Display for Point {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "({}, {})", self.x, self.y)
}
}
// Returns the distance from point p to the line between p1 and p2
fn perpendicular_dista... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #Sidef | Sidef | func perpendicular_distance(Arr start, Arr end, Arr point) {
((point == start) || (point == end)) && return 0
var (Δx, Δy ) = ( end »-« start)...
var (Δpx, Δpy) = (point »-« start)...
var h = hypot(Δx, Δy)
[\Δx, \Δy].map { *_ /= h }
(([Δpx, Δpy] »-« ([Δx, Δy] »*» (Δx*Δpx + Δy*Δpy))) »**» 2).su... |
http://rosettacode.org/wiki/Range_extraction | Range extraction | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #EchoLisp | EchoLisp |
(define task '(0 1 2 4 6 7 8 11 12 14 15 16 17 18 19 20 21 22 23 24 25 27 28 29 30 31 32 33 35 36 37 38 39))
;; 1- GROUPING
(define (group-range item acc)
(if
(or (empty? acc) (!= (caar acc) (1- item)))
(cons (cons item item) acc)
(begin (set-car! (car acc) item) acc)))
;; intermediate result
;; ... |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #Go | Go | package main
import (
"fmt"
"math"
"math/rand"
"strings"
"time"
)
const mean = 1.0
const stdv = .5
const n = 1000
func main() {
var list [n]float64
rand.Seed(time.Now().UnixNano())
for i := range list {
list[i] = mean + stdv*rand.NormFloat64()
}
// show computed mea... |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Quackery | Quackery | typedef unsigned long long u8;
typedef struct ranctx { u8 a; u8 b; u8 c; u8 d; } ranctx;
#define rot(x,k) (((x)<<(k))|((x)>>(64-(k))))
u8 ranval( ranctx *x ) {
u8 e = x->a - rot(x->b, 7);
x->a = x->b ^ rot(x->c, 13);
x->b = x->c + rot(x->d, 37);
x->c = x->d + e;
x->d = e + x->a;
return x->d;
}... |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #R | R | ?RNG
help.search("Distribution", package="stats") |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Racket | Racket | import util::Math;
arbInt(int limit); // generates an arbitrary integer below limit
arbRat(int limit, int limit); // generates an arbitrary rational number between the limits
arbReal(); // generates an arbitrary real value in the interval [0.0, 1.0]
arbSeed(int seed); |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #JavaScript | JavaScript | function parseConfig(config) {
// this expression matches a line starting with an all capital word,
// and anything after it
var regex = /^([A-Z]+)(.*)$/mg;
var configObject = {};
// loop until regex.exec returns null
var match;
while (match = regex.exec(config)) {
// values will ... |
http://rosettacode.org/wiki/Range_expansion | Range expansion | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #Fortran | Fortran | MODULE HOMEONTHERANGE
CONTAINS !The key function.
CHARACTER*200 FUNCTION ERANGE(TEXT) !Expands integer ranges in a list.
Can't return a character value of variable size.
CHARACTER*(*) TEXT !The list on input.
CHARACTER*200 ALINE !Scratchpad for output.
INTEGER N,N1,N2 !Nu... |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Open "input.txt" For Input As #1
Dim line_ As String
While Not Eof(1)
Line Input #1, line_ '' read each line
Print line_ '' echo it to the console
Wend
Close #1
Print
Print "Press any key to quit"
Sleep |
http://rosettacode.org/wiki/Ranking_methods | Ranking methods |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Scala | Scala | object RankingMethods extends App {
case class Score(score: Int, name: String) // incoming data
case class Rank[Precision](rank: Precision, names: List[String]) // outgoing results (can be int or double)
case class State[Precision](n: Int, done: List[Rank[Precision]]) { // internal state, no mutable variabl... |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #PicoLisp | PicoLisp | (pack (flip (chop "äöüÄÖÜß"))) |
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #XPL0 | XPL0 | code Ran=1;
int R;
R:= Ran($7FFF_FFFF) |
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #zkl | zkl | const RANDOM_PATH="/dev/urandom";
fin,buf:=File(RANDOM_PATH,"r"), fin.read(4);
fin.close(); // GC would also close the file
println(buf.toBigEndian(0,4)); // 4 bytes @ offset 0 |
http://rosettacode.org/wiki/Random_Latin_squares | Random Latin squares | A Latin square of size n is an arrangement of n symbols in an n-by-n square in such a way that each row and column has each symbol appearing exactly once.
A randomised Latin square generates random configurations of the symbols for any given n.
Example n=4 randomised Latin square
0 2 3 1
2 1 0 3
3 0 1 2
1 3 2 0
Task... | #Ring | Ring |
load "stdlib.ring"
load "guilib.ring"
###====================================================================================
size = 10
time1 = 0
bwidth = 0
bheight = 0
a2DSquare = newlist(size,size)
a2DFinal = newlist(size,size)
aList = 1:size
aList2 = RandomList(aList)
GenerateRows(aLis... |
http://rosettacode.org/wiki/Random_Latin_squares | Random Latin squares | A Latin square of size n is an arrangement of n symbols in an n-by-n square in such a way that each row and column has each symbol appearing exactly once.
A randomised Latin square generates random configurations of the symbols for any given n.
Example n=4 randomised Latin square
0 2 3 1
2 1 0 3
3 0 1 2
1 3 2 0
Task... | #Ruby | Ruby | N = 5
def generate_square
perms = (1..N).to_a.permutation(N).to_a.shuffle
square = []
N.times do
square << perms.pop
perms.reject!{|perm| perm.zip(square.last).any?{|el1, el2| el1 == el2} }
end
square
end
def print_square(square)
cell_size = N.digits.size + 1
strings = square.map!{|row| row.... |
http://rosettacode.org/wiki/Ray-casting_algorithm | Ray-casting algorithm |
This page uses content from Wikipedia. The original article was at Point_in_polygon. 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)
Given a point and a polygon, check if the point is inside or out... | #Ursala | Ursala | #import flo
in =
@lrzyCipPX ~|afatPRZaq ~&EZ+fleq~~lrPrbr2G&& ~&B+fleq~~lrPrbl2G!| -&
~&Y+ ~~lrPrbl2G fleq,
^E(fleq@lrrPX,@rl fleq\0.)^/~&lr ^(~&r,times)^/minus@llPrll2X vid+ minus~~rbbI&- |
http://rosettacode.org/wiki/Queue/Definition | Queue/Definition |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in the order of insertion.
Operation... | #AWK | AWK | #!/usr/bin/awk -f
BEGIN {
delete q
print "empty? " emptyP()
print "push " push("a")
print "push " push("b")
print "empty? " emptyP()
print "pop " pop()
print "pop " pop()
print "empty? " emptyP()
print "pop " pop()
}
function push(n) {
q[length(q)+1] = n
return n
}
func... |
http://rosettacode.org/wiki/Quaternion_type | Quaternion type | Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number might be -3 + 2i,
wher... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <math.h>
typedef struct quaternion
{
double q[4];
} quaternion_t;
quaternion_t *quaternion_new(void)
{
return malloc(sizeof(quaternion_t));
}
quaternion_t *quaternion_new_set(double q1,
double q2,
double q3,
double q4)
{
q... |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #BASIC | BASIC | 10 LIST |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #E | E | def [reader, writer] := makeQueue()
require(escape empty { reader.dequeue(empty); false } catch _ { true })
writer.enqueue(1)
writer.enqueue(2)
require(reader.dequeue(throw) == 1)
writer.enqueue(3)
require(reader.dequeue(throw) == 2)
require(reader.dequeue(throw) == 3)
require(escape empty { reader.dequeue(empty); fals... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Elena | Elena | import system'collections;
import extensions;
public program()
{
// Create a queue and "push" items into it
var queue := new Queue();
queue.push:1;
queue.push:3;
queue.push:5;
// "Pop" items from the queue in FIFO order
console.printLine(queue.pop()); // 1
console.printLine(queue.p... |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #TorqueScript | TorqueScript | %file = new fileObject();
%file.openForRead("File/Path.txt");
$seventhLine = "";
while(!%file.isEOF())
{
%line++;
if(%line == 7)
{
$seventhLine = %file.readLine();
if($seventhLine $= "")
{
error("Line 7 of the file is blank!");
}
}
}
%file.close();
%file.delete();
if(%line < 7... |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #TUSCRIPT | TUSCRIPT | $$ MODE TUSCRIPT
file="lines.txt"
ERROR/STOP OPEN (file,READ,-std-)
line2fetch=7 |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #EasyLang | EasyLang | func qselect k d[] . res .
#
subr partition
mid = left
for i = left + 1 to right
if d[i] < d[left]
mid += 1
swap d[i] d[mid]
.
.
swap d[left] d[mid]
.
right = len d[] - 1
repeat
call partition
until mid = k
if mid < k
left = mid + 1
else
... |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Elixir | Elixir | defmodule Quick do
def select(k, [x|xs]) do
{ys, zs} = Enum.partition(xs, fn e -> e < x end)
l = length(ys)
cond do
k < l -> select(k, ys)
k > l -> select(k - l - 1, zs)
true -> x
end
end
def test do
v = [9, 8, 7, 6, 5, 0, 1, 2, 3, 4]
Enum.map(0..length(v)-1, fn i -> s... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #Swift | Swift | struct Point: CustomStringConvertible {
let x: Double, y: Double
var description: String {
return "(\(x), \(y))"
}
}
// Returns the distance from point p to the line between p1 and p2
func perpendicularDistance(p: Point, p1: Point, p2: Point) -> Double {
let dx = p2.x - p1.x
let dy = p2.... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #Wren | Wren | import "/dynamic" for Tuple
var Point = Tuple.create("Point", ["x", "y"])
var rdp // recursive
rdp = Fn.new { |l, eps|
var x = 0
var dMax = -1
var p1 = l[0]
var p2 = l[-1]
var x21 = p2.x - p1.x
var y21 = p2.y - p1.y
var i = 0
for (p in l[1..-1]) {
var d = (y21*p.x - x21*p.y +... |
http://rosettacode.org/wiki/Range_extraction | Range extraction | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #Eiffel | Eiffel |
class
RANGE
create
make
feature
make
local
extended_range: STRING
do
extended_range := "0, 1, 2, 4, 6, 7, 8, 11, 12, 14, " +
"15, 16, 17, 18, 19, 20, 21, 22, 23, 24, " +
"25, 27, 28, 29, 30, 31, 32, 33, 35, 36, " +
"37, 38, 39"
print("Extended range: " + extended_ra... |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #Groovy | Groovy | rnd = new Random()
result = (1..1000).inject([]) { r, i -> r << rnd.nextGaussian() } |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #Haskell | Haskell | import System.Random
pairs :: [a] -> [(a,a)]
pairs (x:y:zs) = (x,y):pairs zs
pairs _ = []
gauss mu sigma (r1,r2) =
mu + sigma * sqrt (-2 * log r1) * cos (2 * pi * r2)
gaussians :: (RandomGen g, Random a, Floating a) => Int -> g -> [a]
gaussians n g = take n $ map (gauss 1.0 0.5) $ pairs $ randoms g
re... |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Raku | Raku | import util::Math;
arbInt(int limit); // generates an arbitrary integer below limit
arbRat(int limit, int limit); // generates an arbitrary rational number between the limits
arbReal(); // generates an arbitrary real value in the interval [0.0, 1.0]
arbSeed(int seed); |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Rascal | Rascal | import util::Math;
arbInt(int limit); // generates an arbitrary integer below limit
arbRat(int limit, int limit); // generates an arbitrary rational number between the limits
arbReal(); // generates an arbitrary real value in the interval [0.0, 1.0]
arbSeed(int seed); |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #REXX | REXX | /*(below) returns a random integer between 100 & 200, inclusive.*/
y = random(100, 200) |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Ring | Ring |
nr = 10
for i = 1 to nr
see random(i) + nl
next
|
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Ruby | Ruby | rmd(0) |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #jq | jq | def parse:
def uc: .name | ascii_upcase;
def parse_boolean:
capture( "(?<name>^[^ ] *$)" )
| { (uc) : true };
def parse_var_value:
capture( "(?<name>^[^ ]+)[ =] *(?<value>[^,]+ *$)" )
| { (uc) : .value };
def parse_var_array:
capture( "(?<name>^[^ ]+)[ =] *(?<value>.*)" )
| { (uc... |
http://rosettacode.org/wiki/Range_expansion | Range expansion | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Sub split (s As Const String, sepList As Const String, result() As String)
If s = "" OrElse sepList = "" Then
Redim result(0)
result(0) = s
Return
End If
Dim As Integer i, j, count = 0, empty = 0, length
Dim As Integer position(Len(s) + 1)
position(0) = 0
For i = 0 To l... |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Frink | Frink |
for line = lines["file:yourfile.txt"]
println[line]
|
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Gambas | Gambas | Public Sub Main()
Dim hFile As File
Dim sLine As String
hFile = Open "../InputText.txt" For Input
While Not Eof(hFile)
Line Input #hFile, sLine
Print sLine
Wend
End |
http://rosettacode.org/wiki/Ranking_methods | Ranking methods |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Sidef | Sidef | var scores = [
Pair(Solomon => 44),
Pair(Jason => 42),
Pair(Errol => 42),
Pair(Garry => 41),
Pair(Bernard => 41),
Pair(Barry => 41),
Pair(Stephen => 39),
]
func tiers(s) {
s.group_by { .value }.kv.sort.flip.map { .value.map{.key} }
}
func standard(s) {
var rank = 1
ga... |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #Pike | Pike | reverse("foo"); |
http://rosettacode.org/wiki/Random_Latin_squares | Random Latin squares | A Latin square of size n is an arrangement of n symbols in an n-by-n square in such a way that each row and column has each symbol appearing exactly once.
A randomised Latin square generates random configurations of the symbols for any given n.
Example n=4 randomised Latin square
0 2 3 1
2 1 0 3
3 0 1 2
1 3 2 0
Task... | #Wren | Wren | import "random" for Random
var rand = Random.new()
var printSquare = Fn.new { |latin|
for (row in latin) System.print(row)
System.print()
}
var latinSquare = Fn.new { |n|
if (n <= 0) {
System.print("[]\n")
return
}
var latin = List.filled(n, null)
for (i in 0...n) {
... |
http://rosettacode.org/wiki/Ray-casting_algorithm | Ray-casting algorithm |
This page uses content from Wikipedia. The original article was at Point_in_polygon. 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)
Given a point and a polygon, check if the point is inside or out... | #Visual_Basic_.NET | Visual Basic .NET | Imports System.Math
Module RayCasting
Private square As Integer()() = {New Integer() {0, 0}, New Integer() {20, 0}, New Integer() {20, 20}, New Integer() {0, 20}}
Private squareHole As Integer()() = {New Integer() {0, 0}, New Integer() {20, 0}, New Integer() {20, 20}, New Integer() {0, 20}, New Integer() {5... |
http://rosettacode.org/wiki/Queue/Definition | Queue/Definition |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in the order of insertion.
Operation... | #Batch_File | Batch File |
@echo off
setlocal enableDelayedExpansion
:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
:: FIFO queue usage
:: Define the queue
call :newQueue myQ
:: Populate the queue
for %%A in (value1 value2 value3) do call :enqueue myQ %%A
:: Test if queue is empty by examining the tail "attribute"
if... |
http://rosettacode.org/wiki/Quaternion_type | Quaternion type | Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number might be -3 + 2i,
wher... | #C.23 | C# | using System;
struct Quaternion : IEquatable<Quaternion>
{
public readonly double A, B, C, D;
public Quaternion(double a, double b, double c, double d)
{
this.A = a;
this.B = b;
this.C = c;
this.D = d;
}
public double Norm()
{
return Math.Sqrt(A * A ... |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #Batch_File | Batch File | @type %0 |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Elisa | Elisa |
defmodule Queue do
def empty?([]), do: true
def empty?(_), do: false
def pop([h|t]), do: {h,t}
def push(q,t), do: q ++ [t]
def front([h|_]), do: h
end
|
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Elixir | Elixir |
defmodule Queue do
def empty?([]), do: true
def empty?(_), do: false
def pop([h|t]), do: {h,t}
def push(q,t), do: q ++ [t]
def front([h|_]), do: h
end
|
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Erlang | Erlang | 1> Q = fifo:new().
{fifo,[],[]}
2> fifo:empty(Q).
true
3> Q2 = fifo:push(Q,1).
{fifo,[1],[]}
4> Q3 = fifo:push(Q2,2).
{fifo,[2,1],[]}
5> fifo:empty(Q3).
false
6> fifo:pop(Q3).
{1,{fifo,[],[2]}}
7> {Popped, Q} = fifo:pop(Q2).
{1,{fifo,[],[]}}
8> fifo:pop(fifo:new()).
** exception error: 'empty fifo'
in fun... |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #TXR | TXR | @(skip nil 7)
@line |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #UNIX_Shell | UNIX Shell | get_nth_line() {
local file=$1 n=$2 line
while ((n-- > 0)); do
if ! IFS= read -r line; then
echo "No such line $2 in $file"
return 1
fi
done < "$file"
echo "$line"
}
get_nth_line filename 7 |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Erlang | Erlang |
-module(quickselect).
-export([test/0]).
test() ->
V = [9, 8, 7, 6, 5, 0, 1, 2, 3, 4],
lists:map(
fun(I) -> quickselect(I,V) end,
lists:seq(0, length(V) - 1)
).
quickselect(K, [X | Xs]) ->
{Ys, Zs} =
lists:partition(fun(E) -> E < X end, Xs),
L = length(Ys),
if... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #Yabasic | Yabasic | sub perpendicularDistance(tabla(), i, ini, fin)
local dx, cy, mag, pvx, pvy, pvdot, dsx, dsy, ax, ay
dx = tabla(fin, 1) - tabla(ini, 1)
dy = tabla(fin, 2) - tabla(ini, 2)
//Normalise
mag = (dx^2 + dy^2)^0.5
if mag > 0 dx = dx / mag : dy = dy / mag
pvx = tabla(i, 1) - tabla(ini, 1)
... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #zkl | zkl | fcn perpendicularDistance(start,end, point){ // all are tuples: (x,y) -->|d|
dx,dy := end .zipWith('-,start); // deltas
dpx,dpy := point.zipWith('-,start);
mag := (dx*dx + dy*dy).sqrt();
if(mag>0.0){ dx/=mag; dy/=mag; }
p,dsx,dsy := dx*dpx + dy*dpy, p*dx, p*dy;
((dpx - dsx).pow(2) + (dpy - dsy... |
http://rosettacode.org/wiki/Range_extraction | Range extraction | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #Elixir | Elixir | defmodule RC do
def range_extract(list) do
max = Enum.max(list) + 2
sorted = Enum.sort([max|list])
candidate_number = hd(sorted)
current_number = hd(sorted)
extract(tl(sorted), candidate_number, current_number, [])
end
defp extract([], _, _, range), do: Enum.reverse(range) |> Enum.join(",")
... |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #HicEst | HicEst | REAL :: n=1000, m=1, s=0.5, array(n)
pi = 4 * ATAN(1)
array = s * (-2*LOG(RAN(1)))^0.5 * COS(2*pi*RAN(1)) + m |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #Icon_and_Unicon | Icon and Unicon |
procedure main()
local L
L := list(1000)
every L[1 to 1000] := 1.0 + 0.5 * sqrt(-2.0 * log(?0)) * cos(2.0 * &pi * ?0)
every write(!L)
end
|
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Run_BASIC | Run BASIC | rmd(0) |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Rust | Rust | import scala.util.Random
/**
* Histogram of 200 throws with two dices.
*/
object Throws extends App {
Stream.continually(Random.nextInt(6) + Random.nextInt(6) + 2)
.take(200).groupBy(identity).toList.sortBy(_._1)
.foreach {
case (a, b) => println(f"$a%2d:" + "X" * b.size)
}
} |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Scala | Scala | import scala.util.Random
/**
* Histogram of 200 throws with two dices.
*/
object Throws extends App {
Stream.continually(Random.nextInt(6) + Random.nextInt(6) + 2)
.take(200).groupBy(identity).toList.sortBy(_._1)
.foreach {
case (a, b) => println(f"$a%2d:" + "X" * b.size)
}
} |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #Julia | Julia | function readconf(file)
vars = Dict()
for line in eachline(file)
line = strip(line)
if !isempty(line) && !startswith(line, '#') && !startswith(line, ';')
fspace = searchindex(line, " ")
if fspace == 0
vars[Symbol(lowercase(line))] = true
else
... |
http://rosettacode.org/wiki/Range_expansion | Range expansion | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #Go | Go | package main
import (
"fmt"
"strconv"
"strings"
)
const input = "-6,-3--1,3-5,7-11,14,15,17-20"
func main() {
fmt.Println("range:", input)
var r []int
var last int
for _, part := range strings.Split(input, ",") {
if i := strings.Index(part[1:], "-"); i == -1 {
n, er... |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #GAP | GAP | ReadByLines := function(name)
local file, line, count;
file := InputTextFile(name);
count := 0;
while true do
line := ReadLine(file);
if line = fail then
break;
fi;
count := count + 1;
od;
CloseStream(file);
return count;
end;
# With [http://www.ibiblio.org/pub/docs/misc/amnesty.txt amnesty.txt]
Rea... |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Genie | Genie | [indent=4]
/*
Read file line by line, in Genie
valac readFileLines.gs
./readFileLines [filename]
*/
init
fileName:string
fileName = (args[1] is null) ? "readFileLines.gs" : args[1]
var file = FileStream.open(fileName, "r")
if file is null
stdout.printf("Error: %s did not open\n", ... |
http://rosettacode.org/wiki/Ranking_methods | Ranking methods |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Tcl | Tcl | proc rank {rankingMethod sortedList} {
# Extract the groups in the data (this is pointless for ordinal...)
set s [set group [set groups {}]]
foreach {score who} $sortedList {
if {$score != $s} {
lappend groups [llength $group]
set s $score
set group {}
}
lappend group $who
}
lappen... |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #PL.2FI | PL/I | s = reverse(s); |
http://rosettacode.org/wiki/Random_Latin_squares | Random Latin squares | A Latin square of size n is an arrangement of n symbols in an n-by-n square in such a way that each row and column has each symbol appearing exactly once.
A randomised Latin square generates random configurations of the symbols for any given n.
Example n=4 randomised Latin square
0 2 3 1
2 1 0 3
3 0 1 2
1 3 2 0
Task... | #zkl | zkl | fcn randomLatinSquare(n,symbols=[1..]){ //--> list of lists
if(n<=0) return(T);
square,syms := List(), symbols.walker().walk(n);
do(n){ syms=syms.copy(); square.append(syms.append(syms.pop(0))) }
// shuffle rows, transpose & shuffle columns
T.zip(square.shuffle().xplode()).shuffle();
}
fcn rls2String(sq... |
http://rosettacode.org/wiki/Ray-casting_algorithm | Ray-casting algorithm |
This page uses content from Wikipedia. The original article was at Point_in_polygon. 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)
Given a point and a polygon, check if the point is inside or out... | #Wren | Wren | import "/fmt" for Fmt
class RayCasting {
static intersects(a, b, p) {
if (a[1] > b[1]) return intersects(b, a, p)
if (p[1] == a[1] || p[1] == b[1]) p[1] = p[1] + 0.0001
if (p[1] > b[1] || p[1] < a[1] || p[0] >= a[0].max(b[0])) return false
if (p[0] < a[0].min(b[0])) return true ... |
http://rosettacode.org/wiki/Queue/Definition | Queue/Definition |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in the order of insertion.
Operation... | #BBC_BASIC | BBC BASIC | FIFOSIZE = 1000
FOR n = 3 TO 5
PRINT "Push ";n : PROCenqueue(n)
NEXT
PRINT "Pop " ; FNdequeue
PRINT "Push 6" : PROCenqueue(6)
REPEAT
PRINT "Pop " ; FNdequeue
UNTIL FNisempty
PRINT "Pop " ; FNdequeue
END
DEF PROCenqueue(n) : LOCAL f%
D... |
http://rosettacode.org/wiki/Quaternion_type | Quaternion type | Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number might be -3 + 2i,
wher... | #C.2B.2B | C++ | #include <iostream>
using namespace std;
template<class T = double>
class Quaternion
{
public:
T w, x, y, z;
// Numerical constructor
Quaternion(const T &w, const T &x, const T &y, const T &z): w(w), x(x), y(y), z(z) {};
Quaternion(const T &x, const T &y, const T &z): w(T()), x(x), y(y), z(z) {}; // For 3-r... |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #BBC_BASIC | BBC BASIC | PRINT $(PAGE+22)$(PAGE+21):REM PRINT $(PAGE+22)$(PAGE+21):REM |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Factor | Factor | USING: combinators deques dlists kernel prettyprint ;
IN: rosetta-code.queue-usage
DL{ } clone { ! make new queue
[ [ 1 ] dip push-front ] ! push 1
[ [ 2 ] dip push-front ] ! push 2
[ [ 3 ] dip push-front ] ! push 3
[ . ] ! DL{ 3 2 1 }
[ pop-back drop ] ! p... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Fantom | Fantom |
class Main
{
public static Void main ()
{
q := Queue()
q.push (1)
q.push ("a")
echo ("Is empty? " + q.isEmpty)
echo ("Element: " + q.pop)
echo ("Element: " + q.pop)
echo ("Is empty? " + q.isEmpty)
try { q.pop } catch (Err e) { echo (e.msg) }
}
}
|
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #Ursa | Ursa | decl string<> lines
decl file f
f.open "filename.txt"
set lines (f.readlines)
f.close
if (< (size lines) 7)
out "the file has less than seven lines" endl console
stop
end if
out "the seventh line in the file is:" endl endl console
out lines<6> endl console |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #VBScript | VBScript |
Function read_line(filepath,n)
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set objFile = objFSO.OpenTextFile(filepath,1)
arrLines = Split(objFile.ReadAll,vbCrLf)
If UBound(arrLines) >= n-1 Then
If arrLines(n-1) <> "" Then
read_line = arrLines(n-1)
Else
read_line = "Line " & n & " is null."
... |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #F.23 | F# |
let rec quickselect k list =
match list with
| [] -> failwith "Cannot take largest element of empty list."
| [a] -> a
| x::xs ->
let (ys, zs) = List.partition (fun arg -> arg < x) xs
let l = List.length ys
if k < l then quickselect k ys
elif k > l then quickselect (k-l... |
http://rosettacode.org/wiki/Range_extraction | Range extraction | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #Emacs_Lisp | Emacs Lisp | (require 'gnus-range)
(defun rangext (lst)
(mapconcat (lambda (item)
(if (consp item)
(if (= (+ 1 (car item)) (cdr item))
(format "%d,%d" (car item) (cdr item))
(format "%d-%d" (car item) (cdr item)))
(format "%d" item)))
(gnus-compress-sequence lst)... |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #IDL | IDL | result = 1.0 + 0.5*randomn(seed,1000) |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #J | J | urand=: ?@$ 0:
zrand=: (2 o. 2p1 * urand) * [: %: _2 * [: ^. urand
1 + 0.5 * zrand 100 |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Seed7 | Seed7 | say 1.rand # random float in the interval [0,1)
say 100.irand # random integer in the interval [0,100) |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Sidef | Sidef | say 1.rand # random float in the interval [0,1)
say 100.irand # random integer in the interval [0,100) |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Sparkling | Sparkling | rand |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Standard_ML | Standard ML | rand |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Stata | Stata | rand |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #Kotlin | Kotlin | import java.nio.charset.StandardCharsets
import java.nio.file.Files
import java.nio.file.Paths
data class Configuration(val map: Map<String, Any?>) {
val fullName: String by map
val favoriteFruit: String by map
val needsPeeling: Boolean by map
val otherFamily: List<String> by map
}
fun main(args: Ar... |
http://rosettacode.org/wiki/Range_expansion | Range expansion | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #Groovy | Groovy | def expandRanges = { compressed ->
Eval.me('['+compressed.replaceAll(~/(\d)-/, '$1..')+']').flatten().toString()[1..-2]
} |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Go | Go | package main
import (
"bufio"
"fmt"
"log"
"os"
)
func init() {
log.SetFlags(log.Lshortfile)
}
func main() {
// Open an input file, exit on error.
inputFile, err := os.Open("byline.go")
if err != nil {
log.Fatal("Error opening input file:", err)
}
// Closes the file when we leave the scope of the cur... |
http://rosettacode.org/wiki/Ranking_methods | Ranking methods |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #True_BASIC | True BASIC |
LET n = 7
DIM puntos(7), ptosnom(7), nombre$(7)
SUB MostarTabla
FOR i = 1 to n
PRINT str$(ptosnom(i)); " "; puntos(i); " "; nombre$(i)
NEXT i
PRINT
END SUB
PRINT "Puntuaciones a clasificar (mejores primero):"
FOR i = 1 to n
READ puntos(i), nombre$(i)
PRINT " "; puntos(i); " ";... |
http://rosettacode.org/wiki/Ranking_methods | Ranking methods |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Visual_FoxPro | Visual FoxPro |
#DEFINE CTAB CHR(9)
#DEFINE CRLF CHR(13) + CHR(10)
LOCAL lcTxt As String, i As Integer
CLOSE DATABASES ALL
SET SAFETY OFF
CLEAR
CREATE CURSOR scores (score I, name V(8), rownum I AUTOINC)
INDEX ON score TAG score COLLATE "Machine"
SET ORDER TO 0
INSERT INTO scores (score, name) VALUES (44, "Solomon")
INSERT INTO scor... |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #Plain_English | Plain English | To run:
Start up.
Put "asdf" into a string.
Reverse the string.
Shut down. |
http://rosettacode.org/wiki/Ray-casting_algorithm | Ray-casting algorithm |
This page uses content from Wikipedia. The original article was at Point_in_polygon. 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)
Given a point and a polygon, check if the point is inside or out... | #zkl | zkl | const E = 0.0001;
fcn rayHitsSeg([(Px,Py)],[(Ax,Ay)],[(Bx,By)]){ // --> Bool
if(Py==Ay or Py==By) Py+=E;
if(Py<Ay or Py>By or Px>Ax.max(Bx)) False
else if(Px<Ax.min(Bx)) True
else try{ ( (Py - Ay)/(Px - Ax) )>=( (By - Ay)/(Bx - Ax) ) } //blue>=red
catch(MathError){ Px==Ax } // divide ... |
http://rosettacode.org/wiki/Queue/Definition | Queue/Definition |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in the order of insertion.
Operation... | #BQN | BQN | queue ← {
data ← ⟨⟩
Push ⇐ {data∾˜↩𝕩}
Pop ⇐ {
𝕊𝕩:
0=≠data ? •Show "Cannot pop from empty queue";
(data↓˜↩¯1)⊢⊑⌽data
}
Empty ⇐ {𝕊𝕩: 0=≠data}
Display ⇐ {𝕊𝕩: •Show data}
}
q1 ← queue
•Show q1.Empty@
q1.Push 3
q1.Push 4
q1.Display@
•Show q1.Pop@
q1.Display@ |
http://rosettacode.org/wiki/Quaternion_type | Quaternion type | Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number might be -3 + 2i,
wher... | #CLU | CLU | quat = cluster is make, minus, norm, conj, add, addr, mul, mulr,
equal, get_a, get_b, get_c, get_d, q_form
rep = struct[a,b,c,d: real]
make = proc (a,b,c,d: real) returns (cvt)
return (rep${a:a, b:b, c:c, d:d})
end make
minus = proc (q: cvt) returns (cvt)
return (d... |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #BCPL | BCPL | get "libhdr"
let start() be
$( let x = table
13,10,32,32,32,32,108,101,116,32,110,32,61,32,48,
13,10,32,32,32,32,119,114,105,116,101,115,40,34,103,
101,116,32,42,34,108,105,98,104,100,114,42,34,42,78,
42,78,108,101,116,32,115,116,97,114,116,40,41,32,98,
101,42,78,36,40,32,32,108,101,116,32,120,32... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Forth | Forth | : cqueue: ( n -- <text>)
create \ compile time: build the data structure in memory
dup
dup 1- and abort" queue size must be power of 2"
0 , \ write pointer "HEAD"
0 , ... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Fortran | Fortran | module fifo_nodes
type fifo_node
integer :: datum
! the next part is not variable and must be present
type(fifo_node), pointer :: next
logical :: valid
end type fifo_node
end module fifo_nodes
program FIFOTest
use fifo
implicit none
type(fifo_head) :: thehead
type(fifo_node), dimensi... |
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