INSTRUCTION stringlengths 1 8.43k | RESPONSE stringlengths 75 104k |
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Constructs a OpenAIGPTConfig from a Python dictionary of parameters. | def from_dict(cls, json_object):
"""Constructs a `OpenAIGPTConfig` from a Python dictionary of parameters."""
config = OpenAIGPTConfig(vocab_size_or_config_json_file=-1)
for key, value in json_object.items():
config.__dict__[key] = value
return config |
Update input embeddings with new embedding matrice if needed | def set_num_special_tokens(self, num_special_tokens):
" Update input embeddings with new embedding matrice if needed "
if self.config.n_special == num_special_tokens:
return
# Update config
self.config.n_special = num_special_tokens
# Build new embeddings and initialize all new embeddings (in particular the special tokens)
old_embed = self.tokens_embed
self.tokens_embed = nn.Embedding(self.config.total_tokens_embeddings, self.config.n_embd)
self.tokens_embed.to(old_embed.weight.device)
self.init_weights(self.tokens_embed)
# Copy word embeddings from the previous weights
self.tokens_embed.weight.data[:self.config.vocab_size, :] = old_embed.weight.data[:self.config.vocab_size, :] |
Update input and output embeddings with new embedding matrice Make sure we are sharing the embeddings | def set_num_special_tokens(self, num_special_tokens):
""" Update input and output embeddings with new embedding matrice
Make sure we are sharing the embeddings
"""
self.transformer.set_num_special_tokens(num_special_tokens)
self.lm_head.set_embeddings_weights(self.transformer.tokens_embed.weight) |
Performs a single optimization step. | def step(self, closure=None):
"""Performs a single optimization step.
Arguments:
closure (callable, optional): A closure that reevaluates the model
and returns the loss.
"""
loss = None
if closure is not None:
loss = closure()
for group in self.param_groups:
for p in group['params']:
if p.grad is None:
continue
grad = p.grad.data
if grad.is_sparse:
raise RuntimeError('Adam does not support sparse gradients, please consider SparseAdam instead')
state = self.state[p]
# State initialization
if len(state) == 0:
state['step'] = 0
# Exponential moving average of gradient values
state['exp_avg'] = torch.zeros_like(p.data)
# Exponential moving average of squared gradient values
state['exp_avg_sq'] = torch.zeros_like(p.data)
exp_avg, exp_avg_sq = state['exp_avg'], state['exp_avg_sq']
beta1, beta2 = group['b1'], group['b2']
state['step'] += 1
# Add grad clipping
if group['max_grad_norm'] > 0:
clip_grad_norm_(p, group['max_grad_norm'])
# Decay the first and second moment running average coefficient
exp_avg.mul_(beta1).add_(1 - beta1, grad)
exp_avg_sq.mul_(beta2).addcmul_(1 - beta2, grad, grad)
denom = exp_avg_sq.sqrt().add_(group['e'])
bias_correction1 = 1 - beta1 ** state['step']
bias_correction2 = 1 - beta2 ** state['step']
lr_scheduled = group['lr']
lr_scheduled *= group['schedule'].get_lr(state['step'])
step_size = lr_scheduled * math.sqrt(bias_correction2) / bias_correction1
p.data.addcdiv_(-step_size, exp_avg, denom)
# Add weight decay at the end (fixed version)
if (len(p.size()) > 1 or group['vector_l2']) and group['weight_decay'] > 0:
p.data.add_(-lr_scheduled * group['weight_decay'], p.data)
return loss |
: param step: which of t_total steps we re on: param nowarn: set to True to suppress warning regarding training beyond specified t_total steps: return: learning rate multiplier for current update | def get_lr(self, step, nowarn=False):
"""
:param step: which of t_total steps we're on
:param nowarn: set to True to suppress warning regarding training beyond specified 't_total' steps
:return: learning rate multiplier for current update
"""
if self.t_total < 0:
return 1.
progress = float(step) / self.t_total
ret = self.get_lr_(progress)
# warning for exceeding t_total (only active with warmup_linear
if not nowarn and self.warn_t_total and progress > 1. and progress > self.warned_for_t_total_at_progress:
logger.warning(
"Training beyond specified 't_total'. Learning rate multiplier set to {}. Please set 't_total' of {} correctly."
.format(ret, self.__class__.__name__))
self.warned_for_t_total_at_progress = progress
# end warning
return ret |
Performs a single optimization step. | def step(self, closure=None):
"""Performs a single optimization step.
Arguments:
closure (callable, optional): A closure that reevaluates the model
and returns the loss.
"""
loss = None
if closure is not None:
loss = closure()
for group in self.param_groups:
for p in group['params']:
if p.grad is None:
continue
grad = p.grad.data
if grad.is_sparse:
raise RuntimeError('Adam does not support sparse gradients, please consider SparseAdam instead')
state = self.state[p]
# State initialization
if len(state) == 0:
state['step'] = 0
# Exponential moving average of gradient values
state['next_m'] = torch.zeros_like(p.data)
# Exponential moving average of squared gradient values
state['next_v'] = torch.zeros_like(p.data)
next_m, next_v = state['next_m'], state['next_v']
beta1, beta2 = group['b1'], group['b2']
# Add grad clipping
if group['max_grad_norm'] > 0:
clip_grad_norm_(p, group['max_grad_norm'])
# Decay the first and second moment running average coefficient
# In-place operations to update the averages at the same time
next_m.mul_(beta1).add_(1 - beta1, grad)
next_v.mul_(beta2).addcmul_(1 - beta2, grad, grad)
update = next_m / (next_v.sqrt() + group['e'])
# Just adding the square of the weights to the loss function is *not*
# the correct way of using L2 regularization/weight decay with Adam,
# since that will interact with the m and v parameters in strange ways.
#
# Instead we want to decay the weights in a manner that doesn't interact
# with the m/v parameters. This is equivalent to adding the square
# of the weights to the loss with plain (non-momentum) SGD.
if group['weight_decay'] > 0.0:
update += group['weight_decay'] * p.data
lr_scheduled = group['lr']
lr_scheduled *= group['schedule'].get_lr(state['step'])
update_with_lr = lr_scheduled * update
p.data.add_(-update_with_lr)
state['step'] += 1
# step_size = lr_scheduled * math.sqrt(bias_correction2) / bias_correction1
# No bias correction
# bias_correction1 = 1 - beta1 ** state['step']
# bias_correction2 = 1 - beta2 ** state['step']
return loss |
Runs basic whitespace cleaning and splitting on a piece of text. | def whitespace_tokenize(text):
"""Runs basic whitespace cleaning and splitting on a piece of text."""
text = text.strip()
if not text:
return []
tokens = text.split()
return tokens |
Checks whether chars is a punctuation character. | def _is_punctuation(char):
"""Checks whether `chars` is a punctuation character."""
cp = ord(char)
# We treat all non-letter/number ASCII as punctuation.
# Characters such as "^", "$", and "`" are not in the Unicode
# Punctuation class but we treat them as punctuation anyways, for
# consistency.
if ((cp >= 33 and cp <= 47) or (cp >= 58 and cp <= 64) or
(cp >= 91 and cp <= 96) or (cp >= 123 and cp <= 126)):
return True
cat = unicodedata.category(char)
if cat.startswith("P"):
return True
return False |
Converts a sequence of tokens into ids using the vocab. | def convert_tokens_to_ids(self, tokens):
"""Converts a sequence of tokens into ids using the vocab."""
ids = []
for token in tokens:
ids.append(self.vocab[token])
if len(ids) > self.max_len:
logger.warning(
"Token indices sequence length is longer than the specified maximum "
" sequence length for this BERT model ({} > {}). Running this"
" sequence through BERT will result in indexing errors".format(len(ids), self.max_len)
)
return ids |
Converts a sequence of ids in wordpiece tokens using the vocab. | def convert_ids_to_tokens(self, ids):
"""Converts a sequence of ids in wordpiece tokens using the vocab."""
tokens = []
for i in ids:
tokens.append(self.ids_to_tokens[i])
return tokens |
Save the tokenizer vocabulary to a directory or file. | def save_vocabulary(self, vocab_path):
"""Save the tokenizer vocabulary to a directory or file."""
index = 0
if os.path.isdir(vocab_path):
vocab_file = os.path.join(vocab_path, VOCAB_NAME)
with open(vocab_file, "w", encoding="utf-8") as writer:
for token, token_index in sorted(self.vocab.items(), key=lambda kv: kv[1]):
if index != token_index:
logger.warning("Saving vocabulary to {}: vocabulary indices are not consecutive."
" Please check that the vocabulary is not corrupted!".format(vocab_file))
index = token_index
writer.write(token + u'\n')
index += 1
return vocab_file |
Instantiate a PreTrainedBertModel from a pre - trained model file. Download and cache the pre - trained model file if needed. | def from_pretrained(cls, pretrained_model_name_or_path, cache_dir=None, *inputs, **kwargs):
"""
Instantiate a PreTrainedBertModel from a pre-trained model file.
Download and cache the pre-trained model file if needed.
"""
if pretrained_model_name_or_path in PRETRAINED_VOCAB_ARCHIVE_MAP:
vocab_file = PRETRAINED_VOCAB_ARCHIVE_MAP[pretrained_model_name_or_path]
if '-cased' in pretrained_model_name_or_path and kwargs.get('do_lower_case', True):
logger.warning("The pre-trained model you are loading is a cased model but you have not set "
"`do_lower_case` to False. We are setting `do_lower_case=False` for you but "
"you may want to check this behavior.")
kwargs['do_lower_case'] = False
elif '-cased' not in pretrained_model_name_or_path and not kwargs.get('do_lower_case', True):
logger.warning("The pre-trained model you are loading is an uncased model but you have set "
"`do_lower_case` to False. We are setting `do_lower_case=True` for you "
"but you may want to check this behavior.")
kwargs['do_lower_case'] = True
else:
vocab_file = pretrained_model_name_or_path
if os.path.isdir(vocab_file):
vocab_file = os.path.join(vocab_file, VOCAB_NAME)
# redirect to the cache, if necessary
try:
resolved_vocab_file = cached_path(vocab_file, cache_dir=cache_dir)
except EnvironmentError:
logger.error(
"Model name '{}' was not found in model name list ({}). "
"We assumed '{}' was a path or url but couldn't find any file "
"associated to this path or url.".format(
pretrained_model_name_or_path,
', '.join(PRETRAINED_VOCAB_ARCHIVE_MAP.keys()),
vocab_file))
return None
if resolved_vocab_file == vocab_file:
logger.info("loading vocabulary file {}".format(vocab_file))
else:
logger.info("loading vocabulary file {} from cache at {}".format(
vocab_file, resolved_vocab_file))
if pretrained_model_name_or_path in PRETRAINED_VOCAB_POSITIONAL_EMBEDDINGS_SIZE_MAP:
# if we're using a pretrained model, ensure the tokenizer wont index sequences longer
# than the number of positional embeddings
max_len = PRETRAINED_VOCAB_POSITIONAL_EMBEDDINGS_SIZE_MAP[pretrained_model_name_or_path]
kwargs['max_len'] = min(kwargs.get('max_len', int(1e12)), max_len)
# Instantiate tokenizer.
tokenizer = cls(resolved_vocab_file, *inputs, **kwargs)
return tokenizer |
Tokenizes a piece of text. | def tokenize(self, text):
"""Tokenizes a piece of text."""
text = self._clean_text(text)
# This was added on November 1st, 2018 for the multilingual and Chinese
# models. This is also applied to the English models now, but it doesn't
# matter since the English models were not trained on any Chinese data
# and generally don't have any Chinese data in them (there are Chinese
# characters in the vocabulary because Wikipedia does have some Chinese
# words in the English Wikipedia.).
text = self._tokenize_chinese_chars(text)
orig_tokens = whitespace_tokenize(text)
split_tokens = []
for token in orig_tokens:
if self.do_lower_case and token not in self.never_split:
token = token.lower()
token = self._run_strip_accents(token)
split_tokens.extend(self._run_split_on_punc(token))
output_tokens = whitespace_tokenize(" ".join(split_tokens))
return output_tokens |
Strips accents from a piece of text. | def _run_strip_accents(self, text):
"""Strips accents from a piece of text."""
text = unicodedata.normalize("NFD", text)
output = []
for char in text:
cat = unicodedata.category(char)
if cat == "Mn":
continue
output.append(char)
return "".join(output) |
Adds whitespace around any CJK character. | def _tokenize_chinese_chars(self, text):
"""Adds whitespace around any CJK character."""
output = []
for char in text:
cp = ord(char)
if self._is_chinese_char(cp):
output.append(" ")
output.append(char)
output.append(" ")
else:
output.append(char)
return "".join(output) |
Checks whether CP is the codepoint of a CJK character. | def _is_chinese_char(self, cp):
"""Checks whether CP is the codepoint of a CJK character."""
# This defines a "chinese character" as anything in the CJK Unicode block:
# https://en.wikipedia.org/wiki/CJK_Unified_Ideographs_(Unicode_block)
#
# Note that the CJK Unicode block is NOT all Japanese and Korean characters,
# despite its name. The modern Korean Hangul alphabet is a different block,
# as is Japanese Hiragana and Katakana. Those alphabets are used to write
# space-separated words, so they are not treated specially and handled
# like the all of the other languages.
if ((cp >= 0x4E00 and cp <= 0x9FFF) or #
(cp >= 0x3400 and cp <= 0x4DBF) or #
(cp >= 0x20000 and cp <= 0x2A6DF) or #
(cp >= 0x2A700 and cp <= 0x2B73F) or #
(cp >= 0x2B740 and cp <= 0x2B81F) or #
(cp >= 0x2B820 and cp <= 0x2CEAF) or
(cp >= 0xF900 and cp <= 0xFAFF) or #
(cp >= 0x2F800 and cp <= 0x2FA1F)): #
return True
return False |
Tokenizes a piece of text into its word pieces. | def tokenize(self, text):
"""Tokenizes a piece of text into its word pieces.
This uses a greedy longest-match-first algorithm to perform tokenization
using the given vocabulary.
For example:
input = "unaffable"
output = ["un", "##aff", "##able"]
Args:
text: A single token or whitespace separated tokens. This should have
already been passed through `BasicTokenizer`.
Returns:
A list of wordpiece tokens.
"""
output_tokens = []
for token in whitespace_tokenize(text):
chars = list(token)
if len(chars) > self.max_input_chars_per_word:
output_tokens.append(self.unk_token)
continue
is_bad = False
start = 0
sub_tokens = []
while start < len(chars):
end = len(chars)
cur_substr = None
while start < end:
substr = "".join(chars[start:end])
if start > 0:
substr = "##" + substr
if substr in self.vocab:
cur_substr = substr
break
end -= 1
if cur_substr is None:
is_bad = True
break
sub_tokens.append(cur_substr)
start = end
if is_bad:
output_tokens.append(self.unk_token)
else:
output_tokens.extend(sub_tokens)
return output_tokens |
Output a list of tuples ( story 1st continuation 2nd continuation label ) | def load_rocstories_dataset(dataset_path):
""" Output a list of tuples(story, 1st continuation, 2nd continuation, label) """
with open(dataset_path, encoding='utf_8') as f:
f = csv.reader(f)
output = []
next(f) # skip the first line
for line in tqdm(f):
output.append((' '.join(line[1:5]), line[5], line[6], int(line[-1])-1))
return output |
Pre - process datasets containing lists of tuples ( story 1st continuation 2nd continuation label ) | def pre_process_datasets(encoded_datasets, input_len, cap_length, start_token, delimiter_token, clf_token):
""" Pre-process datasets containing lists of tuples(story, 1st continuation, 2nd continuation, label)
To Transformer inputs of shape (n_batch, n_alternative, length) comprising for each batch, continuation:
input_ids[batch, alternative, :] = [start_token] + story[:cap_length] + [delimiter_token] + cont1[:cap_length] + [clf_token]
"""
tensor_datasets = []
for dataset in encoded_datasets:
n_batch = len(dataset)
input_ids = np.zeros((n_batch, 2, input_len), dtype=np.int64)
mc_token_ids = np.zeros((n_batch, 2), dtype=np.int64)
lm_labels = np.full((n_batch, 2, input_len), fill_value=-1, dtype=np.int64)
mc_labels = np.zeros((n_batch,), dtype=np.int64)
for i, (story, cont1, cont2, mc_label), in enumerate(dataset):
with_cont1 = [start_token] + story[:cap_length] + [delimiter_token] + cont1[:cap_length] + [clf_token]
with_cont2 = [start_token] + story[:cap_length] + [delimiter_token] + cont2[:cap_length] + [clf_token]
input_ids[i, 0, :len(with_cont1)] = with_cont1
input_ids[i, 1, :len(with_cont2)] = with_cont2
mc_token_ids[i, 0] = len(with_cont1) - 1
mc_token_ids[i, 1] = len(with_cont2) - 1
lm_labels[i, 0, :len(with_cont1)-1] = with_cont1[1:]
lm_labels[i, 1, :len(with_cont2)-1] = with_cont2[1:]
mc_labels[i] = mc_label
all_inputs = (input_ids, mc_token_ids, lm_labels, mc_labels)
tensor_datasets.append(tuple(torch.tensor(t) for t in all_inputs))
return tensor_datasets |
Masking some random tokens for Language Model task with probabilities as in the original BERT paper.: param tokens: list of str tokenized sentence.: param tokenizer: Tokenizer object used for tokenization ( we need it s vocab here ): return: ( list of str list of int ) masked tokens and related labels for LM prediction | def random_word(tokens, tokenizer):
"""
Masking some random tokens for Language Model task with probabilities as in the original BERT paper.
:param tokens: list of str, tokenized sentence.
:param tokenizer: Tokenizer, object used for tokenization (we need it's vocab here)
:return: (list of str, list of int), masked tokens and related labels for LM prediction
"""
output_label = []
for i, token in enumerate(tokens):
prob = random.random()
# mask token with 15% probability
if prob < 0.15:
prob /= 0.15
# 80% randomly change token to mask token
if prob < 0.8:
tokens[i] = "[MASK]"
# 10% randomly change token to random token
elif prob < 0.9:
tokens[i] = random.choice(list(tokenizer.vocab.items()))[0]
# -> rest 10% randomly keep current token
# append current token to output (we will predict these later)
try:
output_label.append(tokenizer.vocab[token])
except KeyError:
# For unknown words (should not occur with BPE vocab)
output_label.append(tokenizer.vocab["[UNK]"])
logger.warning("Cannot find token '{}' in vocab. Using [UNK] insetad".format(token))
else:
# no masking token (will be ignored by loss function later)
output_label.append(-1)
return tokens, output_label |
Convert a raw sample ( pair of sentences as tokenized strings ) into a proper training sample with IDs LM labels input_mask CLS and SEP tokens etc.: param example: InputExample containing sentence input as strings and is_next label: param max_seq_length: int maximum length of sequence.: param tokenizer: Tokenizer: return: InputFeatures containing all inputs and labels of one sample as IDs ( as used for model training ) | def convert_example_to_features(example, max_seq_length, tokenizer):
"""
Convert a raw sample (pair of sentences as tokenized strings) into a proper training sample with
IDs, LM labels, input_mask, CLS and SEP tokens etc.
:param example: InputExample, containing sentence input as strings and is_next label
:param max_seq_length: int, maximum length of sequence.
:param tokenizer: Tokenizer
:return: InputFeatures, containing all inputs and labels of one sample as IDs (as used for model training)
"""
tokens_a = example.tokens_a
tokens_b = example.tokens_b
# Modifies `tokens_a` and `tokens_b` in place so that the total
# length is less than the specified length.
# Account for [CLS], [SEP], [SEP] with "- 3"
_truncate_seq_pair(tokens_a, tokens_b, max_seq_length - 3)
tokens_a, t1_label = random_word(tokens_a, tokenizer)
tokens_b, t2_label = random_word(tokens_b, tokenizer)
# concatenate lm labels and account for CLS, SEP, SEP
lm_label_ids = ([-1] + t1_label + [-1] + t2_label + [-1])
# The convention in BERT is:
# (a) For sequence pairs:
# tokens: [CLS] is this jack ##son ##ville ? [SEP] no it is not . [SEP]
# type_ids: 0 0 0 0 0 0 0 0 1 1 1 1 1 1
# (b) For single sequences:
# tokens: [CLS] the dog is hairy . [SEP]
# type_ids: 0 0 0 0 0 0 0
#
# Where "type_ids" are used to indicate whether this is the first
# sequence or the second sequence. The embedding vectors for `type=0` and
# `type=1` were learned during pre-training and are added to the wordpiece
# embedding vector (and position vector). This is not *strictly* necessary
# since the [SEP] token unambigiously separates the sequences, but it makes
# it easier for the model to learn the concept of sequences.
#
# For classification tasks, the first vector (corresponding to [CLS]) is
# used as as the "sentence vector". Note that this only makes sense because
# the entire model is fine-tuned.
tokens = []
segment_ids = []
tokens.append("[CLS]")
segment_ids.append(0)
for token in tokens_a:
tokens.append(token)
segment_ids.append(0)
tokens.append("[SEP]")
segment_ids.append(0)
assert len(tokens_b) > 0
for token in tokens_b:
tokens.append(token)
segment_ids.append(1)
tokens.append("[SEP]")
segment_ids.append(1)
input_ids = tokenizer.convert_tokens_to_ids(tokens)
# The mask has 1 for real tokens and 0 for padding tokens. Only real
# tokens are attended to.
input_mask = [1] * len(input_ids)
# Zero-pad up to the sequence length.
while len(input_ids) < max_seq_length:
input_ids.append(0)
input_mask.append(0)
segment_ids.append(0)
lm_label_ids.append(-1)
assert len(input_ids) == max_seq_length
assert len(input_mask) == max_seq_length
assert len(segment_ids) == max_seq_length
assert len(lm_label_ids) == max_seq_length
if example.guid < 5:
logger.info("*** Example ***")
logger.info("guid: %s" % (example.guid))
logger.info("tokens: %s" % " ".join(
[str(x) for x in tokens]))
logger.info("input_ids: %s" % " ".join([str(x) for x in input_ids]))
logger.info("input_mask: %s" % " ".join([str(x) for x in input_mask]))
logger.info(
"segment_ids: %s" % " ".join([str(x) for x in segment_ids]))
logger.info("LM label: %s " % (lm_label_ids))
logger.info("Is next sentence label: %s " % (example.is_next))
features = InputFeatures(input_ids=input_ids,
input_mask=input_mask,
segment_ids=segment_ids,
lm_label_ids=lm_label_ids,
is_next=example.is_next)
return features |
Get one sample from corpus consisting of two sentences. With prob. 50% these are two subsequent sentences from one doc. With 50% the second sentence will be a random one from another doc.: param index: int index of sample.: return: ( str str int ) sentence 1 sentence 2 isNextSentence Label | def random_sent(self, index):
"""
Get one sample from corpus consisting of two sentences. With prob. 50% these are two subsequent sentences
from one doc. With 50% the second sentence will be a random one from another doc.
:param index: int, index of sample.
:return: (str, str, int), sentence 1, sentence 2, isNextSentence Label
"""
t1, t2 = self.get_corpus_line(index)
if random.random() > 0.5:
label = 0
else:
t2 = self.get_random_line()
label = 1
assert len(t1) > 0
assert len(t2) > 0
return t1, t2, label |
Get one sample from corpus consisting of a pair of two subsequent lines from the same doc.: param item: int index of sample.: return: ( str str ) two subsequent sentences from corpus | def get_corpus_line(self, item):
"""
Get one sample from corpus consisting of a pair of two subsequent lines from the same doc.
:param item: int, index of sample.
:return: (str, str), two subsequent sentences from corpus
"""
t1 = ""
t2 = ""
assert item < self.corpus_lines
if self.on_memory:
sample = self.sample_to_doc[item]
t1 = self.all_docs[sample["doc_id"]][sample["line"]]
t2 = self.all_docs[sample["doc_id"]][sample["line"]+1]
# used later to avoid random nextSentence from same doc
self.current_doc = sample["doc_id"]
return t1, t2
else:
if self.line_buffer is None:
# read first non-empty line of file
while t1 == "" :
t1 = next(self.file).strip()
t2 = next(self.file).strip()
else:
# use t2 from previous iteration as new t1
t1 = self.line_buffer
t2 = next(self.file).strip()
# skip empty rows that are used for separating documents and keep track of current doc id
while t2 == "" or t1 == "":
t1 = next(self.file).strip()
t2 = next(self.file).strip()
self.current_doc = self.current_doc+1
self.line_buffer = t2
assert t1 != ""
assert t2 != ""
return t1, t2 |
Get random line from another document for nextSentence task.: return: str content of one line | def get_random_line(self):
"""
Get random line from another document for nextSentence task.
:return: str, content of one line
"""
# Similar to original tf repo: This outer loop should rarely go for more than one iteration for large
# corpora. However, just to be careful, we try to make sure that
# the random document is not the same as the document we're processing.
for _ in range(10):
if self.on_memory:
rand_doc_idx = random.randint(0, len(self.all_docs)-1)
rand_doc = self.all_docs[rand_doc_idx]
line = rand_doc[random.randrange(len(rand_doc))]
else:
rand_index = random.randint(1, self.corpus_lines if self.corpus_lines < 1000 else 1000)
#pick random line
for _ in range(rand_index):
line = self.get_next_line()
#check if our picked random line is really from another doc like we want it to be
if self.current_random_doc != self.current_doc:
break
return line |
Gets next line of random_file and starts over when reaching end of file | def get_next_line(self):
""" Gets next line of random_file and starts over when reaching end of file"""
try:
line = next(self.random_file).strip()
#keep track of which document we are currently looking at to later avoid having the same doc as t1
if line == "":
self.current_random_doc = self.current_random_doc + 1
line = next(self.random_file).strip()
except StopIteration:
self.random_file.close()
self.random_file = open(self.corpus_path, "r", encoding=self.encoding)
line = next(self.random_file).strip()
return line |
Creates the predictions for the masked LM objective. This is mostly copied from the Google BERT repo but with several refactors to clean it up and remove a lot of unnecessary variables. | def create_masked_lm_predictions(tokens, masked_lm_prob, max_predictions_per_seq, vocab_list):
"""Creates the predictions for the masked LM objective. This is mostly copied from the Google BERT repo, but
with several refactors to clean it up and remove a lot of unnecessary variables."""
cand_indices = []
for (i, token) in enumerate(tokens):
if token == "[CLS]" or token == "[SEP]":
continue
cand_indices.append(i)
num_to_mask = min(max_predictions_per_seq,
max(1, int(round(len(tokens) * masked_lm_prob))))
shuffle(cand_indices)
mask_indices = sorted(sample(cand_indices, num_to_mask))
masked_token_labels = []
for index in mask_indices:
# 80% of the time, replace with [MASK]
if random() < 0.8:
masked_token = "[MASK]"
else:
# 10% of the time, keep original
if random() < 0.5:
masked_token = tokens[index]
# 10% of the time, replace with random word
else:
masked_token = choice(vocab_list)
masked_token_labels.append(tokens[index])
# Once we've saved the true label for that token, we can overwrite it with the masked version
tokens[index] = masked_token
return tokens, mask_indices, masked_token_labels |
This code is mostly a duplicate of the equivalent function from Google BERT s repo. However we make some changes and improvements. Sampling is improved and no longer requires a loop in this function. Also documents are sampled proportionally to the number of sentences they contain which means each sentence ( rather than each document ) has an equal chance of being sampled as a false example for the NextSentence task. | def create_instances_from_document(
doc_database, doc_idx, max_seq_length, short_seq_prob,
masked_lm_prob, max_predictions_per_seq, vocab_list):
"""This code is mostly a duplicate of the equivalent function from Google BERT's repo.
However, we make some changes and improvements. Sampling is improved and no longer requires a loop in this function.
Also, documents are sampled proportionally to the number of sentences they contain, which means each sentence
(rather than each document) has an equal chance of being sampled as a false example for the NextSentence task."""
document = doc_database[doc_idx]
# Account for [CLS], [SEP], [SEP]
max_num_tokens = max_seq_length - 3
# We *usually* want to fill up the entire sequence since we are padding
# to `max_seq_length` anyways, so short sequences are generally wasted
# computation. However, we *sometimes*
# (i.e., short_seq_prob == 0.1 == 10% of the time) want to use shorter
# sequences to minimize the mismatch between pre-training and fine-tuning.
# The `target_seq_length` is just a rough target however, whereas
# `max_seq_length` is a hard limit.
target_seq_length = max_num_tokens
if random() < short_seq_prob:
target_seq_length = randint(2, max_num_tokens)
# We DON'T just concatenate all of the tokens from a document into a long
# sequence and choose an arbitrary split point because this would make the
# next sentence prediction task too easy. Instead, we split the input into
# segments "A" and "B" based on the actual "sentences" provided by the user
# input.
instances = []
current_chunk = []
current_length = 0
i = 0
while i < len(document):
segment = document[i]
current_chunk.append(segment)
current_length += len(segment)
if i == len(document) - 1 or current_length >= target_seq_length:
if current_chunk:
# `a_end` is how many segments from `current_chunk` go into the `A`
# (first) sentence.
a_end = 1
if len(current_chunk) >= 2:
a_end = randrange(1, len(current_chunk))
tokens_a = []
for j in range(a_end):
tokens_a.extend(current_chunk[j])
tokens_b = []
# Random next
if len(current_chunk) == 1 or random() < 0.5:
is_random_next = True
target_b_length = target_seq_length - len(tokens_a)
# Sample a random document, with longer docs being sampled more frequently
random_document = doc_database.sample_doc(current_idx=doc_idx, sentence_weighted=True)
random_start = randrange(0, len(random_document))
for j in range(random_start, len(random_document)):
tokens_b.extend(random_document[j])
if len(tokens_b) >= target_b_length:
break
# We didn't actually use these segments so we "put them back" so
# they don't go to waste.
num_unused_segments = len(current_chunk) - a_end
i -= num_unused_segments
# Actual next
else:
is_random_next = False
for j in range(a_end, len(current_chunk)):
tokens_b.extend(current_chunk[j])
truncate_seq_pair(tokens_a, tokens_b, max_num_tokens)
assert len(tokens_a) >= 1
assert len(tokens_b) >= 1
tokens = ["[CLS]"] + tokens_a + ["[SEP]"] + tokens_b + ["[SEP]"]
# The segment IDs are 0 for the [CLS] token, the A tokens and the first [SEP]
# They are 1 for the B tokens and the final [SEP]
segment_ids = [0 for _ in range(len(tokens_a) + 2)] + [1 for _ in range(len(tokens_b) + 1)]
tokens, masked_lm_positions, masked_lm_labels = create_masked_lm_predictions(
tokens, masked_lm_prob, max_predictions_per_seq, vocab_list)
instance = {
"tokens": tokens,
"segment_ids": segment_ids,
"is_random_next": is_random_next,
"masked_lm_positions": masked_lm_positions,
"masked_lm_labels": masked_lm_labels}
instances.append(instance)
current_chunk = []
current_length = 0
i += 1
return instances |
embedding: an nn. Embedding layer bias: [ n_vocab ] labels: [ b1 b2 ] inputs: [ b1 b2 n_emb ] sampler: you may use a LogUniformSampler Return logits: [ b1 b2 1 + n_sample ] | def sample_logits(embedding, bias, labels, inputs, sampler):
"""
embedding: an nn.Embedding layer
bias: [n_vocab]
labels: [b1, b2]
inputs: [b1, b2, n_emb]
sampler: you may use a LogUniformSampler
Return
logits: [b1, b2, 1 + n_sample]
"""
true_log_probs, samp_log_probs, neg_samples = sampler.sample(labels)
n_sample = neg_samples.size(0)
b1, b2 = labels.size(0), labels.size(1)
all_ids = torch.cat([labels.view(-1), neg_samples])
all_w = embedding(all_ids)
true_w = all_w[: -n_sample].view(b1, b2, -1)
sample_w = all_w[- n_sample:].view(n_sample, -1)
all_b = bias[all_ids]
true_b = all_b[: -n_sample].view(b1, b2)
sample_b = all_b[- n_sample:]
hit = (labels[:, :, None] == neg_samples).detach()
true_logits = torch.einsum('ijk,ijk->ij',
[true_w, inputs]) + true_b - true_log_probs
sample_logits = torch.einsum('lk,ijk->ijl',
[sample_w, inputs]) + sample_b - samp_log_probs
sample_logits.masked_fill_(hit, -1e30)
logits = torch.cat([true_logits[:, :, None], sample_logits], -1)
return logits |
Params: hidden:: [ len * bsz x d_proj ] target:: [ len * bsz ] Return: if target is None: out:: [ len * bsz ] Negative log likelihood else: out:: [ len * bsz x n_tokens ] log probabilities of tokens over the vocabulary We could replace this implementation by the native PyTorch one if their s had an option to set bias on all clusters in the native one. here: https:// github. com/ pytorch/ pytorch/ blob/ dbe6a7a9ff1a364a8706bf5df58a1ca96d2fd9da/ torch/ nn/ modules/ adaptive. py#L138 | def forward(self, hidden, target=None, keep_order=False):
'''
Params:
hidden :: [len*bsz x d_proj]
target :: [len*bsz]
Return:
if target is None:
out :: [len*bsz] Negative log likelihood
else:
out :: [len*bsz x n_tokens] log probabilities of tokens over the vocabulary
We could replace this implementation by the native PyTorch one
if their's had an option to set bias on all clusters in the native one.
here: https://github.com/pytorch/pytorch/blob/dbe6a7a9ff1a364a8706bf5df58a1ca96d2fd9da/torch/nn/modules/adaptive.py#L138
'''
if target is not None:
target = target.view(-1)
if hidden.size(0) != target.size(0):
raise RuntimeError('Input and target should have the same size '
'in the batch dimension.')
if self.n_clusters == 0:
logit = self._compute_logit(hidden, self.out_layers[0].weight,
self.out_layers[0].bias, self.out_projs[0])
if target is not None:
output = -F.log_softmax(logit, dim=-1) \
.gather(1, target.unsqueeze(1)).squeeze(1)
else:
output = F.log_softmax(logit, dim=-1)
else:
# construct weights and biases
weights, biases = [], []
for i in range(len(self.cutoffs)):
if self.div_val == 1:
l_idx, r_idx = self.cutoff_ends[i], self.cutoff_ends[i + 1]
weight_i = self.out_layers[0].weight[l_idx:r_idx]
bias_i = self.out_layers[0].bias[l_idx:r_idx]
else:
weight_i = self.out_layers[i].weight
bias_i = self.out_layers[i].bias
if i == 0:
weight_i = torch.cat(
[weight_i, self.cluster_weight], dim=0)
bias_i = torch.cat(
[bias_i, self.cluster_bias], dim=0)
weights.append(weight_i)
biases.append(bias_i)
head_weight, head_bias, head_proj = weights[0], biases[0], self.out_projs[0]
head_logit = self._compute_logit(hidden, head_weight, head_bias, head_proj)
head_logprob = F.log_softmax(head_logit, dim=1)
if target is None:
out = hidden.new_empty((head_logit.size(0), self.n_token))
else:
out = torch.zeros_like(target, dtype=hidden.dtype, device=hidden.device)
offset = 0
cutoff_values = [0] + self.cutoffs
for i in range(len(cutoff_values) - 1):
l_idx, r_idx = cutoff_values[i], cutoff_values[i + 1]
if target is not None:
mask_i = (target >= l_idx) & (target < r_idx)
indices_i = mask_i.nonzero().squeeze()
if indices_i.numel() == 0:
continue
target_i = target.index_select(0, indices_i) - l_idx
head_logprob_i = head_logprob.index_select(0, indices_i)
hidden_i = hidden.index_select(0, indices_i)
else:
hidden_i = hidden
if i == 0:
if target is not None:
logprob_i = head_logprob_i.gather(1, target_i[:, None]).squeeze(1)
else:
out[:, :self.cutoffs[0]] = head_logprob[:, :self.cutoffs[0]]
else:
weight_i, bias_i, proj_i = weights[i], biases[i], self.out_projs[i]
tail_logit_i = self._compute_logit(hidden_i, weight_i, bias_i, proj_i)
tail_logprob_i = F.log_softmax(tail_logit_i, dim=1)
cluster_prob_idx = self.cutoffs[0] + i - 1 # No probability for the head cluster
if target is not None:
logprob_i = head_logprob_i[:, cluster_prob_idx] \
+ tail_logprob_i.gather(1, target_i[:, None]).squeeze(1)
else:
logprob_i = head_logprob[:, cluster_prob_idx, None] + tail_logprob_i
out[:, l_idx:r_idx] = logprob_i
if target is not None:
if (hasattr(self, 'keep_order') and self.keep_order) or keep_order:
out.index_copy_(0, indices_i, -logprob_i)
else:
out[offset:offset+logprob_i.size(0)].copy_(-logprob_i)
offset += logprob_i.size(0)
return out |
r Computes log probabilities for all: math: n \ _classes From: https:// github. com/ pytorch/ pytorch/ blob/ master/ torch/ nn/ modules/ adaptive. py Args: hidden ( Tensor ): a minibatch of examples Returns: log - probabilities of for each class: math: c in range: math: 0 < = c < = n \ _classes where: math: n \ _classes is a parameter passed to AdaptiveLogSoftmaxWithLoss constructor. Shape: - Input:: math: ( N in \ _features ) - Output:: math: ( N n \ _classes ) | def log_prob(self, hidden):
r""" Computes log probabilities for all :math:`n\_classes`
From: https://github.com/pytorch/pytorch/blob/master/torch/nn/modules/adaptive.py
Args:
hidden (Tensor): a minibatch of examples
Returns:
log-probabilities of for each class :math:`c`
in range :math:`0 <= c <= n\_classes`, where :math:`n\_classes` is a
parameter passed to ``AdaptiveLogSoftmaxWithLoss`` constructor.
Shape:
- Input: :math:`(N, in\_features)`
- Output: :math:`(N, n\_classes)`
"""
if self.n_clusters == 0:
logit = self._compute_logit(hidden, self.out_layers[0].weight,
self.out_layers[0].bias, self.out_projs[0])
return F.log_softmax(logit, dim=-1)
else:
# construct weights and biases
weights, biases = [], []
for i in range(len(self.cutoffs)):
if self.div_val == 1:
l_idx, r_idx = self.cutoff_ends[i], self.cutoff_ends[i + 1]
weight_i = self.out_layers[0].weight[l_idx:r_idx]
bias_i = self.out_layers[0].bias[l_idx:r_idx]
else:
weight_i = self.out_layers[i].weight
bias_i = self.out_layers[i].bias
if i == 0:
weight_i = torch.cat(
[weight_i, self.cluster_weight], dim=0)
bias_i = torch.cat(
[bias_i, self.cluster_bias], dim=0)
weights.append(weight_i)
biases.append(bias_i)
head_weight, head_bias, head_proj = weights[0], biases[0], self.out_projs[0]
head_logit = self._compute_logit(hidden, head_weight, head_bias, head_proj)
out = hidden.new_empty((head_logit.size(0), self.n_token))
head_logprob = F.log_softmax(head_logit, dim=1)
cutoff_values = [0] + self.cutoffs
for i in range(len(cutoff_values) - 1):
start_idx, stop_idx = cutoff_values[i], cutoff_values[i + 1]
if i == 0:
out[:, :self.cutoffs[0]] = head_logprob[:, :self.cutoffs[0]]
else:
weight_i, bias_i, proj_i = weights[i], biases[i], self.out_projs[i]
tail_logit_i = self._compute_logit(hidden, weight_i, bias_i, proj_i)
tail_logprob_i = F.log_softmax(tail_logit_i, dim=1)
logprob_i = head_logprob[:, -i] + tail_logprob_i
out[:, start_idx, stop_idx] = logprob_i
return out |
labels: [ b1 b2 ] Return true_log_probs: [ b1 b2 ] samp_log_probs: [ n_sample ] neg_samples: [ n_sample ] | def sample(self, labels):
"""
labels: [b1, b2]
Return
true_log_probs: [b1, b2]
samp_log_probs: [n_sample]
neg_samples: [n_sample]
"""
# neg_samples = torch.empty(0).long()
n_sample = self.n_sample
n_tries = 2 * n_sample
with torch.no_grad():
neg_samples = torch.multinomial(self.dist, n_tries, replacement=True).unique()
device = labels.device
neg_samples = neg_samples.to(device)
true_log_probs = self.log_q[labels].to(device)
samp_log_probs = self.log_q[neg_samples].to(device)
return true_log_probs, samp_log_probs, neg_samples |
A map of modules from TF to PyTorch. This time I use a map to keep the PyTorch model as identical to the original PyTorch model as possible. | def build_tf_to_pytorch_map(model, config):
""" A map of modules from TF to PyTorch.
This time I use a map to keep the PyTorch model as identical to the original PyTorch model as possible.
"""
tf_to_pt_map = {}
if hasattr(model, 'transformer'):
# We are loading in a TransfoXLLMHeadModel => we will load also the Adaptive Softmax
tf_to_pt_map.update({
"transformer/adaptive_softmax/cutoff_0/cluster_W": model.crit.cluster_weight,
"transformer/adaptive_softmax/cutoff_0/cluster_b": model.crit.cluster_bias})
for i, (out_l, proj_l, tie_proj) in enumerate(zip(
model.crit.out_layers,
model.crit.out_projs,
config.tie_projs)):
layer_str = "transformer/adaptive_softmax/cutoff_%d/" % i
if config.tie_weight:
tf_to_pt_map.update({
layer_str + 'b': out_l.bias})
else:
raise NotImplementedError
# I don't think this is implemented in the TF code
tf_to_pt_map.update({
layer_str + 'lookup_table': out_l.weight,
layer_str + 'b': out_l.bias})
if not tie_proj:
tf_to_pt_map.update({
layer_str + 'proj': proj_l
})
# Now load the rest of the transformer
model = model.transformer
# Embeddings
for i, (embed_l, proj_l) in enumerate(zip(model.word_emb.emb_layers, model.word_emb.emb_projs)):
layer_str = "transformer/adaptive_embed/cutoff_%d/" % i
tf_to_pt_map.update({
layer_str + 'lookup_table': embed_l.weight,
layer_str + 'proj_W': proj_l
})
# Transformer blocks
for i, b in enumerate(model.layers):
layer_str = "transformer/layer_%d/" % i
tf_to_pt_map.update({
layer_str + "rel_attn/LayerNorm/gamma": b.dec_attn.layer_norm.weight,
layer_str + "rel_attn/LayerNorm/beta": b.dec_attn.layer_norm.bias,
layer_str + "rel_attn/o/kernel": b.dec_attn.o_net.weight,
layer_str + "rel_attn/qkv/kernel": b.dec_attn.qkv_net.weight,
layer_str + "rel_attn/r/kernel": b.dec_attn.r_net.weight,
layer_str + "ff/LayerNorm/gamma": b.pos_ff.layer_norm.weight,
layer_str + "ff/LayerNorm/beta": b.pos_ff.layer_norm.bias,
layer_str + "ff/layer_1/kernel": b.pos_ff.CoreNet[0].weight,
layer_str + "ff/layer_1/bias": b.pos_ff.CoreNet[0].bias,
layer_str + "ff/layer_2/kernel": b.pos_ff.CoreNet[3].weight,
layer_str + "ff/layer_2/bias": b.pos_ff.CoreNet[3].bias,
})
# Relative positioning biases
if config.untie_r:
r_r_list = []
r_w_list = []
for b in model.layers:
r_r_list.append(b.dec_attn.r_r_bias)
r_w_list.append(b.dec_attn.r_w_bias)
else:
r_r_list = [model.r_r_bias]
r_w_list = [model.r_w_bias]
tf_to_pt_map.update({
'transformer/r_r_bias': r_r_list,
'transformer/r_w_bias': r_w_list})
return tf_to_pt_map |
Load tf checkpoints in a pytorch model | def load_tf_weights_in_transfo_xl(model, config, tf_path):
""" Load tf checkpoints in a pytorch model
"""
try:
import numpy as np
import tensorflow as tf
except ImportError:
print("Loading a TensorFlow models in PyTorch, requires TensorFlow to be installed. Please see "
"https://www.tensorflow.org/install/ for installation instructions.")
raise
# Build TF to PyTorch weights loading map
tf_to_pt_map = build_tf_to_pytorch_map(model, config)
# Load weights from TF model
init_vars = tf.train.list_variables(tf_path)
tf_weights = {}
for name, shape in init_vars:
print("Loading TF weight {} with shape {}".format(name, shape))
array = tf.train.load_variable(tf_path, name)
tf_weights[name] = array
for name, pointer in tf_to_pt_map.items():
assert name in tf_weights
array = tf_weights[name]
# adam_v and adam_m are variables used in AdamWeightDecayOptimizer to calculated m and v
# which are not required for using pretrained model
if 'kernel' in name or 'proj' in name:
array = np.transpose(array)
if ('r_r_bias' in name or 'r_w_bias' in name) and len(pointer) > 1:
# Here we will split the TF weigths
assert len(pointer) == array.shape[0]
for i, p_i in enumerate(pointer):
arr_i = array[i, ...]
try:
assert p_i.shape == arr_i.shape
except AssertionError as e:
e.args += (p_i.shape, arr_i.shape)
raise
print("Initialize PyTorch weight {} for layer {}".format(name, i))
p_i.data = torch.from_numpy(arr_i)
else:
try:
assert pointer.shape == array.shape
except AssertionError as e:
e.args += (pointer.shape, array.shape)
raise
print("Initialize PyTorch weight {}".format(name))
pointer.data = torch.from_numpy(array)
tf_weights.pop(name, None)
tf_weights.pop(name + '/Adam', None)
tf_weights.pop(name + '/Adam_1', None)
print("Weights not copied to PyTorch model: {}".format(', '.join(tf_weights.keys())))
return model |
Initialize the weights. | def init_weights(self, m):
""" Initialize the weights.
"""
classname = m.__class__.__name__
if classname.find('Linear') != -1:
if hasattr(m, 'weight') and m.weight is not None:
self.init_weight(m.weight)
if hasattr(m, 'bias') and m.bias is not None:
self.init_bias(m.bias)
elif classname.find('AdaptiveEmbedding') != -1:
if hasattr(m, 'emb_projs'):
for i in range(len(m.emb_projs)):
if m.emb_projs[i] is not None:
nn.init.normal_(m.emb_projs[i], 0.0, self.config.proj_init_std)
elif classname.find('Embedding') != -1:
if hasattr(m, 'weight'):
self.init_weight(m.weight)
elif classname.find('ProjectedAdaptiveLogSoftmax') != -1:
if hasattr(m, 'cluster_weight') and m.cluster_weight is not None:
self.init_weight(m.cluster_weight)
if hasattr(m, 'cluster_bias') and m.cluster_bias is not None:
self.init_bias(m.cluster_bias)
if hasattr(m, 'out_projs'):
for i in range(len(m.out_projs)):
if m.out_projs[i] is not None:
nn.init.normal_(m.out_projs[i], 0.0, self.config.proj_init_std)
elif classname.find('LayerNorm') != -1:
if hasattr(m, 'weight'):
nn.init.normal_(m.weight, 1.0, self.config.init_std)
if hasattr(m, 'bias') and m.bias is not None:
self.init_bias(m.bias)
elif classname.find('TransformerLM') != -1:
if hasattr(m, 'r_emb'):
self.init_weight(m.r_emb)
if hasattr(m, 'r_w_bias'):
self.init_weight(m.r_w_bias)
if hasattr(m, 'r_r_bias'):
self.init_weight(m.r_r_bias)
if hasattr(m, 'r_bias'):
self.init_bias(m.r_bias) |
Instantiate a TransfoXLPreTrainedModel from a pre - trained model file or a pytorch state dict. Download and cache the pre - trained model file if needed. | def from_pretrained(cls, pretrained_model_name_or_path, state_dict=None, cache_dir=None,
from_tf=False, *inputs, **kwargs):
"""
Instantiate a TransfoXLPreTrainedModel from a pre-trained model file or a pytorch state dict.
Download and cache the pre-trained model file if needed.
Params:
pretrained_model_name_or_path: either:
- a str with the name of a pre-trained model to load selected in the list of:
. `transfo-xl`
- a path or url to a pretrained model archive containing:
. `transfo_xl_config.json` a configuration file for the model
. `pytorch_model.bin` a PyTorch dump of a TransfoXLModel instance
- a path or url to a pretrained model archive containing:
. `bert_config.json` a configuration file for the model
. `model.chkpt` a TensorFlow checkpoint
from_tf: should we load the weights from a locally saved TensorFlow checkpoint
cache_dir: an optional path to a folder in which the pre-trained models will be cached.
state_dict: an optional state dictionnary (collections.OrderedDict object) to use instead of pre-trained models
*inputs, **kwargs: additional input for the specific Bert class
(ex: num_labels for BertForSequenceClassification)
"""
if pretrained_model_name_or_path in PRETRAINED_MODEL_ARCHIVE_MAP:
archive_file = PRETRAINED_MODEL_ARCHIVE_MAP[pretrained_model_name_or_path]
config_file = PRETRAINED_CONFIG_ARCHIVE_MAP[pretrained_model_name_or_path]
else:
archive_file = os.path.join(pretrained_model_name_or_path, WEIGHTS_NAME)
config_file = os.path.join(pretrained_model_name_or_path, CONFIG_NAME)
# redirect to the cache, if necessary
try:
resolved_archive_file = cached_path(archive_file, cache_dir=cache_dir)
resolved_config_file = cached_path(config_file, cache_dir=cache_dir)
except EnvironmentError:
logger.error(
"Model name '{}' was not found in model name list ({}). "
"We assumed '{}' was a path or url but couldn't find files {} and {} "
"at this path or url.".format(
pretrained_model_name_or_path,
', '.join(PRETRAINED_MODEL_ARCHIVE_MAP.keys()),
pretrained_model_name_or_path,
archive_file, config_file))
return None
if resolved_archive_file == archive_file and resolved_config_file == config_file:
logger.info("loading weights file {}".format(archive_file))
logger.info("loading configuration file {}".format(config_file))
else:
logger.info("loading weights file {} from cache at {}".format(
archive_file, resolved_archive_file))
logger.info("loading configuration file {} from cache at {}".format(
config_file, resolved_config_file))
# Load config
config = TransfoXLConfig.from_json_file(resolved_config_file)
logger.info("Model config {}".format(config))
# Instantiate model.
model = cls(config, *inputs, **kwargs)
if state_dict is None and not from_tf:
state_dict = torch.load(resolved_archive_file, map_location='cpu')
if from_tf:
# Directly load from a TensorFlow checkpoint
return load_tf_weights_in_transfo_xl(model, config, pretrained_model_name_or_path)
missing_keys = []
unexpected_keys = []
error_msgs = []
# copy state_dict so _load_from_state_dict can modify it
metadata = getattr(state_dict, '_metadata', None)
state_dict = state_dict.copy()
if metadata is not None:
state_dict._metadata = metadata
def load(module, prefix=''):
local_metadata = {} if metadata is None else metadata.get(prefix[:-1], {})
module._load_from_state_dict(
state_dict, prefix, local_metadata, True, missing_keys, unexpected_keys, error_msgs)
for name, child in module._modules.items():
if child is not None:
load(child, prefix + name + '.')
start_prefix = ''
if not hasattr(model, 'transformer') and any(s.startswith('transformer.') for s in state_dict.keys()):
start_prefix = 'transformer.'
load(model, prefix=start_prefix)
if len(missing_keys) > 0:
logger.info("Weights of {} not initialized from pretrained model: {}".format(
model.__class__.__name__, missing_keys))
if len(unexpected_keys) > 0:
logger.info("Weights from pretrained model not used in {}: {}".format(
model.__class__.__name__, unexpected_keys))
if len(error_msgs) > 0:
raise RuntimeError('Error(s) in loading state_dict for {}:\n\t{}'.format(
model.__class__.__name__, "\n\t".join(error_msgs)))
# Make sure we are still sharing the input and output embeddings
if hasattr(model, 'tie_weights'):
model.tie_weights()
return model |
Params: input_ids:: [ bsz len ] mems:: optional mems from previous forwar passes ( or init_mems ) list ( num layers ) of mem states at the entry of each layer shape:: [ self. config. mem_len bsz self. config. d_model ] Note that the first two dimensions are transposed in mems with regards to input_ids and target Returns: tuple ( last_hidden new_mems ) where: new_mems: list ( num layers ) of mem states at the entry of each layer shape:: [ self. config. mem_len bsz self. config. d_model ] last_hidden: output of the last layer: shape:: [ bsz len self. config. d_model ] | def forward(self, input_ids, mems=None):
""" Params:
input_ids :: [bsz, len]
mems :: optional mems from previous forwar passes (or init_mems)
list (num layers) of mem states at the entry of each layer
shape :: [self.config.mem_len, bsz, self.config.d_model]
Note that the first two dimensions are transposed in `mems` with regards to `input_ids` and `target`
Returns:
tuple (last_hidden, new_mems) where:
new_mems: list (num layers) of mem states at the entry of each layer
shape :: [self.config.mem_len, bsz, self.config.d_model]
last_hidden: output of the last layer:
shape :: [bsz, len, self.config.d_model]
"""
# the original code for Transformer-XL used shapes [len, bsz] but we want a unified interface in the library
# so we transpose here from shape [bsz, len] to shape [len, bsz]
input_ids = input_ids.transpose(0, 1).contiguous()
if mems is None:
mems = self.init_mems(input_ids)
last_hidden, new_mems = self._forward(input_ids, mems=mems)
# We transpose back here to shape [bsz, len, hidden_dim]
last_hidden = last_hidden.transpose(0, 1).contiguous()
return (last_hidden, new_mems) |
Run this to be sure output and input ( adaptive ) softmax weights are tied | def tie_weights(self):
""" Run this to be sure output and input (adaptive) softmax weights are tied """
# sampled softmax
if self.sample_softmax > 0:
if self.config.tie_weight:
self.out_layer.weight = self.transformer.word_emb.weight
# adaptive softmax (including standard softmax)
else:
if self.config.tie_weight:
for i in range(len(self.crit.out_layers)):
self.crit.out_layers[i].weight = self.transformer.word_emb.emb_layers[i].weight
if self.config.tie_projs:
for i, tie_proj in enumerate(self.config.tie_projs):
if tie_proj and self.config.div_val == 1 and self.config.d_model != self.config.d_embed:
self.crit.out_projs[i] = self.transformer.word_emb.emb_projs[0]
elif tie_proj and self.config.div_val != 1:
self.crit.out_projs[i] = self.transformer.word_emb.emb_projs[i] |
Params: input_ids:: [ bsz len ] target:: [ bsz len ] Returns: tuple ( softmax_output new_mems ) where: new_mems: list ( num layers ) of hidden states at the entry of each layer shape:: [ mem_len bsz self. config. d_model ]:: Warning: shapes are transposed here w. regards to input_ids softmax_output: output of the ( adaptive ) softmax: if target is None: Negative log likelihood of shape:: [ bsz len ] else: log probabilities of tokens shape:: [ bsz len n_tokens ] | def forward(self, input_ids, target=None, mems=None):
""" Params:
input_ids :: [bsz, len]
target :: [bsz, len]
Returns:
tuple(softmax_output, new_mems) where:
new_mems: list (num layers) of hidden states at the entry of each layer
shape :: [mem_len, bsz, self.config.d_model] :: Warning: shapes are transposed here w. regards to input_ids
softmax_output: output of the (adaptive) softmax:
if target is None:
Negative log likelihood of shape :: [bsz, len]
else:
log probabilities of tokens, shape :: [bsz, len, n_tokens]
"""
bsz = input_ids.size(0)
tgt_len = input_ids.size(1)
last_hidden, new_mems = self.transformer(input_ids, mems)
pred_hid = last_hidden[:, -tgt_len:]
if self.sample_softmax > 0 and self.training:
assert self.config.tie_weight
logit = sample_logits(self.transformer.word_emb, self.out_layer.bias, target, pred_hid, self.sampler)
softmax_output = -F.log_softmax(logit, -1)[:, :, 0]
else:
softmax_output = self.crit(pred_hid.view(-1, pred_hid.size(-1)), target)
if target is None:
softmax_output = softmax_output.view(bsz, tgt_len, -1)
else:
softmax_output = softmax_output.view(bsz, tgt_len)
# We transpose back
return (softmax_output, new_mems) |
Return DateOffset object from string or tuple representation or datetime. timedelta object | def to_offset(freq):
"""
Return DateOffset object from string or tuple representation
or datetime.timedelta object
Parameters
----------
freq : str, tuple, datetime.timedelta, DateOffset or None
Returns
-------
DateOffset
None if freq is None.
Raises
------
ValueError
If freq is an invalid frequency
See Also
--------
DateOffset
Examples
--------
>>> to_offset('5min')
<5 * Minutes>
>>> to_offset('1D1H')
<25 * Hours>
>>> to_offset(('W', 2))
<2 * Weeks: weekday=6>
>>> to_offset((2, 'B'))
<2 * BusinessDays>
>>> to_offset(datetime.timedelta(days=1))
<Day>
>>> to_offset(Hour())
<Hour>
"""
if freq is None:
return None
if isinstance(freq, DateOffset):
return freq
if isinstance(freq, tuple):
name = freq[0]
stride = freq[1]
if isinstance(stride, str):
name, stride = stride, name
name, _ = libfreqs._base_and_stride(name)
delta = get_offset(name) * stride
elif isinstance(freq, timedelta):
delta = None
freq = Timedelta(freq)
try:
for name in freq.components._fields:
offset = _name_to_offset_map[name]
stride = getattr(freq.components, name)
if stride != 0:
offset = stride * offset
if delta is None:
delta = offset
else:
delta = delta + offset
except Exception:
raise ValueError(libfreqs.INVALID_FREQ_ERR_MSG.format(freq))
else:
delta = None
stride_sign = None
try:
splitted = re.split(libfreqs.opattern, freq)
if splitted[-1] != '' and not splitted[-1].isspace():
# the last element must be blank
raise ValueError('last element must be blank')
for sep, stride, name in zip(splitted[0::4], splitted[1::4],
splitted[2::4]):
if sep != '' and not sep.isspace():
raise ValueError('separator must be spaces')
prefix = libfreqs._lite_rule_alias.get(name) or name
if stride_sign is None:
stride_sign = -1 if stride.startswith('-') else 1
if not stride:
stride = 1
if prefix in Resolution._reso_str_bump_map.keys():
stride, name = Resolution.get_stride_from_decimal(
float(stride), prefix
)
stride = int(stride)
offset = get_offset(name)
offset = offset * int(np.fabs(stride) * stride_sign)
if delta is None:
delta = offset
else:
delta = delta + offset
except Exception:
raise ValueError(libfreqs.INVALID_FREQ_ERR_MSG.format(freq))
if delta is None:
raise ValueError(libfreqs.INVALID_FREQ_ERR_MSG.format(freq))
return delta |
Return DateOffset object associated with rule name | def get_offset(name):
"""
Return DateOffset object associated with rule name
Examples
--------
get_offset('EOM') --> BMonthEnd(1)
"""
if name not in libfreqs._dont_uppercase:
name = name.upper()
name = libfreqs._lite_rule_alias.get(name, name)
name = libfreqs._lite_rule_alias.get(name.lower(), name)
else:
name = libfreqs._lite_rule_alias.get(name, name)
if name not in _offset_map:
try:
split = name.split('-')
klass = prefix_mapping[split[0]]
# handles case where there's no suffix (and will TypeError if too
# many '-')
offset = klass._from_name(*split[1:])
except (ValueError, TypeError, KeyError):
# bad prefix or suffix
raise ValueError(libfreqs.INVALID_FREQ_ERR_MSG.format(name))
# cache
_offset_map[name] = offset
return _offset_map[name] |
Infer the most likely frequency given the input index. If the frequency is uncertain a warning will be printed. | def infer_freq(index, warn=True):
"""
Infer the most likely frequency given the input index. If the frequency is
uncertain, a warning will be printed.
Parameters
----------
index : DatetimeIndex or TimedeltaIndex
if passed a Series will use the values of the series (NOT THE INDEX)
warn : boolean, default True
Returns
-------
str or None
None if no discernible frequency
TypeError if the index is not datetime-like
ValueError if there are less than three values.
"""
import pandas as pd
if isinstance(index, ABCSeries):
values = index._values
if not (is_datetime64_dtype(values) or
is_timedelta64_dtype(values) or
values.dtype == object):
raise TypeError("cannot infer freq from a non-convertible dtype "
"on a Series of {dtype}".format(dtype=index.dtype))
index = values
if is_period_arraylike(index):
raise TypeError("PeriodIndex given. Check the `freq` attribute "
"instead of using infer_freq.")
elif is_timedelta64_dtype(index):
# Allow TimedeltaIndex and TimedeltaArray
inferer = _TimedeltaFrequencyInferer(index, warn=warn)
return inferer.get_freq()
if isinstance(index, pd.Index) and not isinstance(index, pd.DatetimeIndex):
if isinstance(index, (pd.Int64Index, pd.Float64Index)):
raise TypeError("cannot infer freq from a non-convertible index "
"type {type}".format(type=type(index)))
index = index.values
if not isinstance(index, pd.DatetimeIndex):
try:
index = pd.DatetimeIndex(index)
except AmbiguousTimeError:
index = pd.DatetimeIndex(index.asi8)
inferer = _FrequencyInferer(index, warn=warn)
return inferer.get_freq() |
Find the appropriate frequency string to describe the inferred frequency of self. values | def get_freq(self):
"""
Find the appropriate frequency string to describe the inferred
frequency of self.values
Returns
-------
str or None
"""
if not self.is_monotonic or not self.index._is_unique:
return None
delta = self.deltas[0]
if _is_multiple(delta, _ONE_DAY):
return self._infer_daily_rule()
# Business hourly, maybe. 17: one day / 65: one weekend
if self.hour_deltas in ([1, 17], [1, 65], [1, 17, 65]):
return 'BH'
# Possibly intraday frequency. Here we use the
# original .asi8 values as the modified values
# will not work around DST transitions. See #8772
elif not self.is_unique_asi8:
return None
delta = self.deltas_asi8[0]
if _is_multiple(delta, _ONE_HOUR):
# Hours
return _maybe_add_count('H', delta / _ONE_HOUR)
elif _is_multiple(delta, _ONE_MINUTE):
# Minutes
return _maybe_add_count('T', delta / _ONE_MINUTE)
elif _is_multiple(delta, _ONE_SECOND):
# Seconds
return _maybe_add_count('S', delta / _ONE_SECOND)
elif _is_multiple(delta, _ONE_MILLI):
# Milliseconds
return _maybe_add_count('L', delta / _ONE_MILLI)
elif _is_multiple(delta, _ONE_MICRO):
# Microseconds
return _maybe_add_count('U', delta / _ONE_MICRO)
else:
# Nanoseconds
return _maybe_add_count('N', delta) |
load a pickle with a provided encoding | def load(fh, encoding=None, is_verbose=False):
"""load a pickle, with a provided encoding
if compat is True:
fake the old class hierarchy
if it works, then return the new type objects
Parameters
----------
fh : a filelike object
encoding : an optional encoding
is_verbose : show exception output
"""
try:
fh.seek(0)
if encoding is not None:
up = Unpickler(fh, encoding=encoding)
else:
up = Unpickler(fh)
up.is_verbose = is_verbose
return up.load()
except (ValueError, TypeError):
raise |
This is called upon unpickling rather than the default which doesn t have arguments and breaks __new__. | def _new_Index(cls, d):
"""
This is called upon unpickling, rather than the default which doesn't
have arguments and breaks __new__.
"""
# required for backward compat, because PI can't be instantiated with
# ordinals through __new__ GH #13277
if issubclass(cls, ABCPeriodIndex):
from pandas.core.indexes.period import _new_PeriodIndex
return _new_PeriodIndex(cls, **d)
return cls.__new__(cls, **d) |
Construct an index from sequences of data. | def ensure_index_from_sequences(sequences, names=None):
"""
Construct an index from sequences of data.
A single sequence returns an Index. Many sequences returns a
MultiIndex.
Parameters
----------
sequences : sequence of sequences
names : sequence of str
Returns
-------
index : Index or MultiIndex
Examples
--------
>>> ensure_index_from_sequences([[1, 2, 3]], names=['name'])
Int64Index([1, 2, 3], dtype='int64', name='name')
>>> ensure_index_from_sequences([['a', 'a'], ['a', 'b']],
names=['L1', 'L2'])
MultiIndex(levels=[['a'], ['a', 'b']],
codes=[[0, 0], [0, 1]],
names=['L1', 'L2'])
See Also
--------
ensure_index
"""
from .multi import MultiIndex
if len(sequences) == 1:
if names is not None:
names = names[0]
return Index(sequences[0], name=names)
else:
return MultiIndex.from_arrays(sequences, names=names) |
Ensure that we have an index from some index - like object. | def ensure_index(index_like, copy=False):
"""
Ensure that we have an index from some index-like object.
Parameters
----------
index : sequence
An Index or other sequence
copy : bool
Returns
-------
index : Index or MultiIndex
Examples
--------
>>> ensure_index(['a', 'b'])
Index(['a', 'b'], dtype='object')
>>> ensure_index([('a', 'a'), ('b', 'c')])
Index([('a', 'a'), ('b', 'c')], dtype='object')
>>> ensure_index([['a', 'a'], ['b', 'c']])
MultiIndex(levels=[['a'], ['b', 'c']],
codes=[[0, 0], [0, 1]])
See Also
--------
ensure_index_from_sequences
"""
if isinstance(index_like, Index):
if copy:
index_like = index_like.copy()
return index_like
if hasattr(index_like, 'name'):
return Index(index_like, name=index_like.name, copy=copy)
if is_iterator(index_like):
index_like = list(index_like)
# must check for exactly list here because of strict type
# check in clean_index_list
if isinstance(index_like, list):
if type(index_like) != list:
index_like = list(index_like)
converted, all_arrays = lib.clean_index_list(index_like)
if len(converted) > 0 and all_arrays:
from .multi import MultiIndex
return MultiIndex.from_arrays(converted)
else:
index_like = converted
else:
# clean_index_list does the equivalent of copying
# so only need to do this if not list instance
if copy:
from copy import copy
index_like = copy(index_like)
return Index(index_like) |
Trims zeros and decimal points. | def _trim_front(strings):
"""
Trims zeros and decimal points.
"""
trimmed = strings
while len(strings) > 0 and all(x[0] == ' ' for x in trimmed):
trimmed = [x[1:] for x in trimmed]
return trimmed |
We require that we have a dtype compat for the values. If we are passed a non - dtype compat then coerce using the constructor. | def _simple_new(cls, values, name=None, dtype=None, **kwargs):
"""
We require that we have a dtype compat for the values. If we are passed
a non-dtype compat, then coerce using the constructor.
Must be careful not to recurse.
"""
if not hasattr(values, 'dtype'):
if (values is None or not len(values)) and dtype is not None:
values = np.empty(0, dtype=dtype)
else:
values = np.array(values, copy=False)
if is_object_dtype(values):
values = cls(values, name=name, dtype=dtype,
**kwargs)._ndarray_values
if isinstance(values, (ABCSeries, ABCIndexClass)):
# Index._data must always be an ndarray.
# This is no-copy for when _values is an ndarray,
# which should be always at this point.
values = np.asarray(values._values)
result = object.__new__(cls)
result._data = values
# _index_data is a (temporary?) fix to ensure that the direct data
# manipulation we do in `_libs/reduction.pyx` continues to work.
# We need access to the actual ndarray, since we're messing with
# data buffers and strides. We don't re-use `_ndarray_values`, since
# we actually set this value too.
result._index_data = values
result.name = name
for k, v in kwargs.items():
setattr(result, k, v)
return result._reset_identity() |
Create a new Index inferring the class with passed value don t copy the data use the same object attributes with passed in attributes taking precedence. | def _shallow_copy_with_infer(self, values, **kwargs):
"""
Create a new Index inferring the class with passed value, don't copy
the data, use the same object attributes with passed in attributes
taking precedence.
*this is an internal non-public method*
Parameters
----------
values : the values to create the new Index, optional
kwargs : updates the default attributes for this Index
"""
attributes = self._get_attributes_dict()
attributes.update(kwargs)
attributes['copy'] = False
if not len(values) and 'dtype' not in kwargs:
attributes['dtype'] = self.dtype
if self._infer_as_myclass:
try:
return self._constructor(values, **attributes)
except (TypeError, ValueError):
pass
return Index(values, **attributes) |
More flexible faster check like is but that works through views. | def is_(self, other):
"""
More flexible, faster check like ``is`` but that works through views.
Note: this is *not* the same as ``Index.identical()``, which checks
that metadata is also the same.
Parameters
----------
other : object
other object to compare against.
Returns
-------
True if both have same underlying data, False otherwise : bool
"""
# use something other than None to be clearer
return self._id is getattr(
other, '_id', Ellipsis) and self._id is not None |
Internal method to handle NA filling of take. | def _assert_take_fillable(self, values, indices, allow_fill=True,
fill_value=None, na_value=np.nan):
"""
Internal method to handle NA filling of take.
"""
indices = ensure_platform_int(indices)
# only fill if we are passing a non-None fill_value
if allow_fill and fill_value is not None:
if (indices < -1).any():
msg = ('When allow_fill=True and fill_value is not None, '
'all indices must be >= -1')
raise ValueError(msg)
taken = algos.take(values,
indices,
allow_fill=allow_fill,
fill_value=na_value)
else:
taken = values.take(indices)
return taken |
Return the formatted data as a unicode string. | def _format_data(self, name=None):
"""
Return the formatted data as a unicode string.
"""
# do we want to justify (only do so for non-objects)
is_justify = not (self.inferred_type in ('string', 'unicode') or
(self.inferred_type == 'categorical' and
is_object_dtype(self.categories)))
return format_object_summary(self, self._formatter_func,
is_justify=is_justify, name=name) |
Render a string representation of the Index. | def format(self, name=False, formatter=None, **kwargs):
"""
Render a string representation of the Index.
"""
header = []
if name:
header.append(pprint_thing(self.name,
escape_chars=('\t', '\r', '\n')) if
self.name is not None else '')
if formatter is not None:
return header + list(self.map(formatter))
return self._format_with_header(header, **kwargs) |
Format specified values of self and return them. | def to_native_types(self, slicer=None, **kwargs):
"""
Format specified values of `self` and return them.
Parameters
----------
slicer : int, array-like
An indexer into `self` that specifies which values
are used in the formatting process.
kwargs : dict
Options for specifying how the values should be formatted.
These options include the following:
1) na_rep : str
The value that serves as a placeholder for NULL values
2) quoting : bool or None
Whether or not there are quoted values in `self`
3) date_format : str
The format used to represent date-like values
"""
values = self
if slicer is not None:
values = values[slicer]
return values._format_native_types(**kwargs) |
Actually format specific types of the index. | def _format_native_types(self, na_rep='', quoting=None, **kwargs):
"""
Actually format specific types of the index.
"""
mask = isna(self)
if not self.is_object() and not quoting:
values = np.asarray(self).astype(str)
else:
values = np.array(self, dtype=object, copy=True)
values[mask] = na_rep
return values |
Return a summarized representation. | def _summary(self, name=None):
"""
Return a summarized representation.
Parameters
----------
name : str
name to use in the summary representation
Returns
-------
String with a summarized representation of the index
"""
if len(self) > 0:
head = self[0]
if hasattr(head, 'format') and not isinstance(head, str):
head = head.format()
tail = self[-1]
if hasattr(tail, 'format') and not isinstance(tail, str):
tail = tail.format()
index_summary = ', %s to %s' % (pprint_thing(head),
pprint_thing(tail))
else:
index_summary = ''
if name is None:
name = type(self).__name__
return '%s: %s entries%s' % (name, len(self), index_summary) |
Return a summarized representation. | def summary(self, name=None):
"""
Return a summarized representation.
.. deprecated:: 0.23.0
"""
warnings.warn("'summary' is deprecated and will be removed in a "
"future version.", FutureWarning, stacklevel=2)
return self._summary(name) |
Create a Series with both index and values equal to the index keys useful with map for returning an indexer based on an index. | def to_series(self, index=None, name=None):
"""
Create a Series with both index and values equal to the index keys
useful with map for returning an indexer based on an index.
Parameters
----------
index : Index, optional
index of resulting Series. If None, defaults to original index
name : string, optional
name of resulting Series. If None, defaults to name of original
index
Returns
-------
Series : dtype will be based on the type of the Index values.
"""
from pandas import Series
if index is None:
index = self._shallow_copy()
if name is None:
name = self.name
return Series(self.values.copy(), index=index, name=name) |
Create a DataFrame with a column containing the Index. | def to_frame(self, index=True, name=None):
"""
Create a DataFrame with a column containing the Index.
.. versionadded:: 0.24.0
Parameters
----------
index : boolean, default True
Set the index of the returned DataFrame as the original Index.
name : object, default None
The passed name should substitute for the index name (if it has
one).
Returns
-------
DataFrame
DataFrame containing the original Index data.
See Also
--------
Index.to_series : Convert an Index to a Series.
Series.to_frame : Convert Series to DataFrame.
Examples
--------
>>> idx = pd.Index(['Ant', 'Bear', 'Cow'], name='animal')
>>> idx.to_frame()
animal
animal
Ant Ant
Bear Bear
Cow Cow
By default, the original Index is reused. To enforce a new Index:
>>> idx.to_frame(index=False)
animal
0 Ant
1 Bear
2 Cow
To override the name of the resulting column, specify `name`:
>>> idx.to_frame(index=False, name='zoo')
zoo
0 Ant
1 Bear
2 Cow
"""
from pandas import DataFrame
if name is None:
name = self.name or 0
result = DataFrame({name: self._values.copy()})
if index:
result.index = self
return result |
Handles the quirks of having a singular name parameter for general Index and plural names parameter for MultiIndex. | def _validate_names(self, name=None, names=None, deep=False):
"""
Handles the quirks of having a singular 'name' parameter for general
Index and plural 'names' parameter for MultiIndex.
"""
from copy import deepcopy
if names is not None and name is not None:
raise TypeError("Can only provide one of `names` and `name`")
elif names is None and name is None:
return deepcopy(self.names) if deep else self.names
elif names is not None:
if not is_list_like(names):
raise TypeError("Must pass list-like as `names`.")
return names
else:
if not is_list_like(name):
return [name]
return name |
Set new names on index. Each name has to be a hashable type. | def _set_names(self, values, level=None):
"""
Set new names on index. Each name has to be a hashable type.
Parameters
----------
values : str or sequence
name(s) to set
level : int, level name, or sequence of int/level names (default None)
If the index is a MultiIndex (hierarchical), level(s) to set (None
for all levels). Otherwise level must be None
Raises
------
TypeError if each name is not hashable.
"""
if not is_list_like(values):
raise ValueError('Names must be a list-like')
if len(values) != 1:
raise ValueError('Length of new names must be 1, got %d' %
len(values))
# GH 20527
# All items in 'name' need to be hashable:
for name in values:
if not is_hashable(name):
raise TypeError('{}.name must be a hashable type'
.format(self.__class__.__name__))
self.name = values[0] |
Set Index or MultiIndex name. | def set_names(self, names, level=None, inplace=False):
"""
Set Index or MultiIndex name.
Able to set new names partially and by level.
Parameters
----------
names : label or list of label
Name(s) to set.
level : int, label or list of int or label, optional
If the index is a MultiIndex, level(s) to set (None for all
levels). Otherwise level must be None.
inplace : bool, default False
Modifies the object directly, instead of creating a new Index or
MultiIndex.
Returns
-------
Index
The same type as the caller or None if inplace is True.
See Also
--------
Index.rename : Able to set new names without level.
Examples
--------
>>> idx = pd.Index([1, 2, 3, 4])
>>> idx
Int64Index([1, 2, 3, 4], dtype='int64')
>>> idx.set_names('quarter')
Int64Index([1, 2, 3, 4], dtype='int64', name='quarter')
>>> idx = pd.MultiIndex.from_product([['python', 'cobra'],
... [2018, 2019]])
>>> idx
MultiIndex(levels=[['cobra', 'python'], [2018, 2019]],
codes=[[1, 1, 0, 0], [0, 1, 0, 1]])
>>> idx.set_names(['kind', 'year'], inplace=True)
>>> idx
MultiIndex(levels=[['cobra', 'python'], [2018, 2019]],
codes=[[1, 1, 0, 0], [0, 1, 0, 1]],
names=['kind', 'year'])
>>> idx.set_names('species', level=0)
MultiIndex(levels=[['cobra', 'python'], [2018, 2019]],
codes=[[1, 1, 0, 0], [0, 1, 0, 1]],
names=['species', 'year'])
"""
if level is not None and not isinstance(self, ABCMultiIndex):
raise ValueError('Level must be None for non-MultiIndex')
if level is not None and not is_list_like(level) and is_list_like(
names):
msg = "Names must be a string when a single level is provided."
raise TypeError(msg)
if not is_list_like(names) and level is None and self.nlevels > 1:
raise TypeError("Must pass list-like as `names`.")
if not is_list_like(names):
names = [names]
if level is not None and not is_list_like(level):
level = [level]
if inplace:
idx = self
else:
idx = self._shallow_copy()
idx._set_names(names, level=level)
if not inplace:
return idx |
Alter Index or MultiIndex name. | def rename(self, name, inplace=False):
"""
Alter Index or MultiIndex name.
Able to set new names without level. Defaults to returning new index.
Length of names must match number of levels in MultiIndex.
Parameters
----------
name : label or list of labels
Name(s) to set.
inplace : boolean, default False
Modifies the object directly, instead of creating a new Index or
MultiIndex.
Returns
-------
Index
The same type as the caller or None if inplace is True.
See Also
--------
Index.set_names : Able to set new names partially and by level.
Examples
--------
>>> idx = pd.Index(['A', 'C', 'A', 'B'], name='score')
>>> idx.rename('grade')
Index(['A', 'C', 'A', 'B'], dtype='object', name='grade')
>>> idx = pd.MultiIndex.from_product([['python', 'cobra'],
... [2018, 2019]],
... names=['kind', 'year'])
>>> idx
MultiIndex(levels=[['cobra', 'python'], [2018, 2019]],
codes=[[1, 1, 0, 0], [0, 1, 0, 1]],
names=['kind', 'year'])
>>> idx.rename(['species', 'year'])
MultiIndex(levels=[['cobra', 'python'], [2018, 2019]],
codes=[[1, 1, 0, 0], [0, 1, 0, 1]],
names=['species', 'year'])
>>> idx.rename('species')
Traceback (most recent call last):
TypeError: Must pass list-like as `names`.
"""
return self.set_names([name], inplace=inplace) |
Validate index level. | def _validate_index_level(self, level):
"""
Validate index level.
For single-level Index getting level number is a no-op, but some
verification must be done like in MultiIndex.
"""
if isinstance(level, int):
if level < 0 and level != -1:
raise IndexError("Too many levels: Index has only 1 level,"
" %d is not a valid level number" % (level, ))
elif level > 0:
raise IndexError("Too many levels:"
" Index has only 1 level, not %d" %
(level + 1))
elif level != self.name:
raise KeyError('Level %s must be same as name (%s)' %
(level, self.name)) |
For internal compatibility with with the Index API. | def sortlevel(self, level=None, ascending=True, sort_remaining=None):
"""
For internal compatibility with with the Index API.
Sort the Index. This is for compat with MultiIndex
Parameters
----------
ascending : boolean, default True
False to sort in descending order
level, sort_remaining are compat parameters
Returns
-------
Index
"""
return self.sort_values(return_indexer=True, ascending=ascending) |
Return index with requested level ( s ) removed. | def droplevel(self, level=0):
"""
Return index with requested level(s) removed.
If resulting index has only 1 level left, the result will be
of Index type, not MultiIndex.
.. versionadded:: 0.23.1 (support for non-MultiIndex)
Parameters
----------
level : int, str, or list-like, default 0
If a string is given, must be the name of a level
If list-like, elements must be names or indexes of levels.
Returns
-------
Index or MultiIndex
"""
if not isinstance(level, (tuple, list)):
level = [level]
levnums = sorted(self._get_level_number(lev) for lev in level)[::-1]
if len(level) == 0:
return self
if len(level) >= self.nlevels:
raise ValueError("Cannot remove {} levels from an index with {} "
"levels: at least one level must be "
"left.".format(len(level), self.nlevels))
# The two checks above guarantee that here self is a MultiIndex
new_levels = list(self.levels)
new_codes = list(self.codes)
new_names = list(self.names)
for i in levnums:
new_levels.pop(i)
new_codes.pop(i)
new_names.pop(i)
if len(new_levels) == 1:
# set nan if needed
mask = new_codes[0] == -1
result = new_levels[0].take(new_codes[0])
if mask.any():
result = result.putmask(mask, np.nan)
result.name = new_names[0]
return result
else:
from .multi import MultiIndex
return MultiIndex(levels=new_levels, codes=new_codes,
names=new_names, verify_integrity=False) |
Return if each value is NaN. | def _isnan(self):
"""
Return if each value is NaN.
"""
if self._can_hold_na:
return isna(self)
else:
# shouldn't reach to this condition by checking hasnans beforehand
values = np.empty(len(self), dtype=np.bool_)
values.fill(False)
return values |
Extract duplicated index elements. | def get_duplicates(self):
"""
Extract duplicated index elements.
.. deprecated:: 0.23.0
Use idx[idx.duplicated()].unique() instead
Returns a sorted list of index elements which appear more than once in
the index.
Returns
-------
array-like
List of duplicated indexes.
See Also
--------
Index.duplicated : Return boolean array denoting duplicates.
Index.drop_duplicates : Return Index with duplicates removed.
Examples
--------
Works on different Index of types.
>>> pd.Index([1, 2, 2, 3, 3, 3, 4]).get_duplicates() # doctest: +SKIP
[2, 3]
Note that for a DatetimeIndex, it does not return a list but a new
DatetimeIndex:
>>> dates = pd.to_datetime(['2018-01-01', '2018-01-02', '2018-01-03',
... '2018-01-03', '2018-01-04', '2018-01-04'],
... format='%Y-%m-%d')
>>> pd.Index(dates).get_duplicates() # doctest: +SKIP
DatetimeIndex(['2018-01-03', '2018-01-04'],
dtype='datetime64[ns]', freq=None)
Sorts duplicated elements even when indexes are unordered.
>>> pd.Index([1, 2, 3, 2, 3, 4, 3]).get_duplicates() # doctest: +SKIP
[2, 3]
Return empty array-like structure when all elements are unique.
>>> pd.Index([1, 2, 3, 4]).get_duplicates() # doctest: +SKIP
[]
>>> dates = pd.to_datetime(['2018-01-01', '2018-01-02', '2018-01-03'],
... format='%Y-%m-%d')
>>> pd.Index(dates).get_duplicates() # doctest: +SKIP
DatetimeIndex([], dtype='datetime64[ns]', freq=None)
"""
warnings.warn("'get_duplicates' is deprecated and will be removed in "
"a future release. You can use "
"idx[idx.duplicated()].unique() instead",
FutureWarning, stacklevel=2)
return self[self.duplicated()].unique() |
Returns an index containing unique values. | def _get_unique_index(self, dropna=False):
"""
Returns an index containing unique values.
Parameters
----------
dropna : bool
If True, NaN values are dropped.
Returns
-------
uniques : index
"""
if self.is_unique and not dropna:
return self
values = self.values
if not self.is_unique:
values = self.unique()
if dropna:
try:
if self.hasnans:
values = values[~isna(values)]
except NotImplementedError:
pass
return self._shallow_copy(values) |
If the result of a set operation will be self return self unless the name changes in which case make a shallow copy of self. | def _get_reconciled_name_object(self, other):
"""
If the result of a set operation will be self,
return self, unless the name changes, in which
case make a shallow copy of self.
"""
name = get_op_result_name(self, other)
if self.name != name:
return self._shallow_copy(name=name)
return self |
Form the union of two Index objects. | def union(self, other, sort=None):
"""
Form the union of two Index objects.
Parameters
----------
other : Index or array-like
sort : bool or None, default None
Whether to sort the resulting Index.
* None : Sort the result, except when
1. `self` and `other` are equal.
2. `self` or `other` has length 0.
3. Some values in `self` or `other` cannot be compared.
A RuntimeWarning is issued in this case.
* False : do not sort the result.
.. versionadded:: 0.24.0
.. versionchanged:: 0.24.1
Changed the default value from ``True`` to ``None``
(without change in behaviour).
Returns
-------
union : Index
Examples
--------
>>> idx1 = pd.Index([1, 2, 3, 4])
>>> idx2 = pd.Index([3, 4, 5, 6])
>>> idx1.union(idx2)
Int64Index([1, 2, 3, 4, 5, 6], dtype='int64')
"""
self._validate_sort_keyword(sort)
self._assert_can_do_setop(other)
other = ensure_index(other)
if len(other) == 0 or self.equals(other):
return self._get_reconciled_name_object(other)
if len(self) == 0:
return other._get_reconciled_name_object(self)
# TODO: is_dtype_union_equal is a hack around
# 1. buggy set ops with duplicates (GH #13432)
# 2. CategoricalIndex lacking setops (GH #10186)
# Once those are fixed, this workaround can be removed
if not is_dtype_union_equal(self.dtype, other.dtype):
this = self.astype('O')
other = other.astype('O')
return this.union(other, sort=sort)
# TODO(EA): setops-refactor, clean all this up
if is_period_dtype(self) or is_datetime64tz_dtype(self):
lvals = self._ndarray_values
else:
lvals = self._values
if is_period_dtype(other) or is_datetime64tz_dtype(other):
rvals = other._ndarray_values
else:
rvals = other._values
if sort is None and self.is_monotonic and other.is_monotonic:
try:
result = self._outer_indexer(lvals, rvals)[0]
except TypeError:
# incomparable objects
result = list(lvals)
# worth making this faster? a very unusual case
value_set = set(lvals)
result.extend([x for x in rvals if x not in value_set])
else:
indexer = self.get_indexer(other)
indexer, = (indexer == -1).nonzero()
if len(indexer) > 0:
other_diff = algos.take_nd(rvals, indexer,
allow_fill=False)
result = _concat._concat_compat((lvals, other_diff))
else:
result = lvals
if sort is None:
try:
result = sorting.safe_sort(result)
except TypeError as e:
warnings.warn("{}, sort order is undefined for "
"incomparable objects".format(e),
RuntimeWarning, stacklevel=3)
# for subclasses
return self._wrap_setop_result(other, result) |
Form the intersection of two Index objects. | def intersection(self, other, sort=False):
"""
Form the intersection of two Index objects.
This returns a new Index with elements common to the index and `other`.
Parameters
----------
other : Index or array-like
sort : False or None, default False
Whether to sort the resulting index.
* False : do not sort the result.
* None : sort the result, except when `self` and `other` are equal
or when the values cannot be compared.
.. versionadded:: 0.24.0
.. versionchanged:: 0.24.1
Changed the default from ``True`` to ``False``, to match
the behaviour of 0.23.4 and earlier.
Returns
-------
intersection : Index
Examples
--------
>>> idx1 = pd.Index([1, 2, 3, 4])
>>> idx2 = pd.Index([3, 4, 5, 6])
>>> idx1.intersection(idx2)
Int64Index([3, 4], dtype='int64')
"""
self._validate_sort_keyword(sort)
self._assert_can_do_setop(other)
other = ensure_index(other)
if self.equals(other):
return self._get_reconciled_name_object(other)
if not is_dtype_equal(self.dtype, other.dtype):
this = self.astype('O')
other = other.astype('O')
return this.intersection(other, sort=sort)
# TODO(EA): setops-refactor, clean all this up
if is_period_dtype(self):
lvals = self._ndarray_values
else:
lvals = self._values
if is_period_dtype(other):
rvals = other._ndarray_values
else:
rvals = other._values
if self.is_monotonic and other.is_monotonic:
try:
result = self._inner_indexer(lvals, rvals)[0]
return self._wrap_setop_result(other, result)
except TypeError:
pass
try:
indexer = Index(rvals).get_indexer(lvals)
indexer = indexer.take((indexer != -1).nonzero()[0])
except Exception:
# duplicates
indexer = algos.unique1d(
Index(rvals).get_indexer_non_unique(lvals)[0])
indexer = indexer[indexer != -1]
taken = other.take(indexer)
if sort is None:
taken = sorting.safe_sort(taken.values)
if self.name != other.name:
name = None
else:
name = self.name
return self._shallow_copy(taken, name=name)
if self.name != other.name:
taken.name = None
return taken |
Return a new Index with elements from the index that are not in other. | def difference(self, other, sort=None):
"""
Return a new Index with elements from the index that are not in
`other`.
This is the set difference of two Index objects.
Parameters
----------
other : Index or array-like
sort : False or None, default None
Whether to sort the resulting index. By default, the
values are attempted to be sorted, but any TypeError from
incomparable elements is caught by pandas.
* None : Attempt to sort the result, but catch any TypeErrors
from comparing incomparable elements.
* False : Do not sort the result.
.. versionadded:: 0.24.0
.. versionchanged:: 0.24.1
Changed the default value from ``True`` to ``None``
(without change in behaviour).
Returns
-------
difference : Index
Examples
--------
>>> idx1 = pd.Index([2, 1, 3, 4])
>>> idx2 = pd.Index([3, 4, 5, 6])
>>> idx1.difference(idx2)
Int64Index([1, 2], dtype='int64')
>>> idx1.difference(idx2, sort=False)
Int64Index([2, 1], dtype='int64')
"""
self._validate_sort_keyword(sort)
self._assert_can_do_setop(other)
if self.equals(other):
# pass an empty np.ndarray with the appropriate dtype
return self._shallow_copy(self._data[:0])
other, result_name = self._convert_can_do_setop(other)
this = self._get_unique_index()
indexer = this.get_indexer(other)
indexer = indexer.take((indexer != -1).nonzero()[0])
label_diff = np.setdiff1d(np.arange(this.size), indexer,
assume_unique=True)
the_diff = this.values.take(label_diff)
if sort is None:
try:
the_diff = sorting.safe_sort(the_diff)
except TypeError:
pass
return this._shallow_copy(the_diff, name=result_name, freq=None) |
Compute the symmetric difference of two Index objects. | def symmetric_difference(self, other, result_name=None, sort=None):
"""
Compute the symmetric difference of two Index objects.
Parameters
----------
other : Index or array-like
result_name : str
sort : False or None, default None
Whether to sort the resulting index. By default, the
values are attempted to be sorted, but any TypeError from
incomparable elements is caught by pandas.
* None : Attempt to sort the result, but catch any TypeErrors
from comparing incomparable elements.
* False : Do not sort the result.
.. versionadded:: 0.24.0
.. versionchanged:: 0.24.1
Changed the default value from ``True`` to ``None``
(without change in behaviour).
Returns
-------
symmetric_difference : Index
Notes
-----
``symmetric_difference`` contains elements that appear in either
``idx1`` or ``idx2`` but not both. Equivalent to the Index created by
``idx1.difference(idx2) | idx2.difference(idx1)`` with duplicates
dropped.
Examples
--------
>>> idx1 = pd.Index([1, 2, 3, 4])
>>> idx2 = pd.Index([2, 3, 4, 5])
>>> idx1.symmetric_difference(idx2)
Int64Index([1, 5], dtype='int64')
You can also use the ``^`` operator:
>>> idx1 ^ idx2
Int64Index([1, 5], dtype='int64')
"""
self._validate_sort_keyword(sort)
self._assert_can_do_setop(other)
other, result_name_update = self._convert_can_do_setop(other)
if result_name is None:
result_name = result_name_update
this = self._get_unique_index()
other = other._get_unique_index()
indexer = this.get_indexer(other)
# {this} minus {other}
common_indexer = indexer.take((indexer != -1).nonzero()[0])
left_indexer = np.setdiff1d(np.arange(this.size), common_indexer,
assume_unique=True)
left_diff = this.values.take(left_indexer)
# {other} minus {this}
right_indexer = (indexer == -1).nonzero()[0]
right_diff = other.values.take(right_indexer)
the_diff = _concat._concat_compat([left_diff, right_diff])
if sort is None:
try:
the_diff = sorting.safe_sort(the_diff)
except TypeError:
pass
attribs = self._get_attributes_dict()
attribs['name'] = result_name
if 'freq' in attribs:
attribs['freq'] = None
return self._shallow_copy_with_infer(the_diff, **attribs) |
Fallback pad/ backfill get_indexer that works for monotonic decreasing indexes and non - monotonic targets. | def _get_fill_indexer_searchsorted(self, target, method, limit=None):
"""
Fallback pad/backfill get_indexer that works for monotonic decreasing
indexes and non-monotonic targets.
"""
if limit is not None:
raise ValueError('limit argument for %r method only well-defined '
'if index and target are monotonic' % method)
side = 'left' if method == 'pad' else 'right'
# find exact matches first (this simplifies the algorithm)
indexer = self.get_indexer(target)
nonexact = (indexer == -1)
indexer[nonexact] = self._searchsorted_monotonic(target[nonexact],
side)
if side == 'left':
# searchsorted returns "indices into a sorted array such that,
# if the corresponding elements in v were inserted before the
# indices, the order of a would be preserved".
# Thus, we need to subtract 1 to find values to the left.
indexer[nonexact] -= 1
# This also mapped not found values (values of 0 from
# np.searchsorted) to -1, which conveniently is also our
# sentinel for missing values
else:
# Mark indices to the right of the largest value as not found
indexer[indexer == len(self)] = -1
return indexer |
Get the indexer for the nearest index labels ; requires an index with values that can be subtracted from each other ( e. g. not strings or tuples ). | def _get_nearest_indexer(self, target, limit, tolerance):
"""
Get the indexer for the nearest index labels; requires an index with
values that can be subtracted from each other (e.g., not strings or
tuples).
"""
left_indexer = self.get_indexer(target, 'pad', limit=limit)
right_indexer = self.get_indexer(target, 'backfill', limit=limit)
target = np.asarray(target)
left_distances = abs(self.values[left_indexer] - target)
right_distances = abs(self.values[right_indexer] - target)
op = operator.lt if self.is_monotonic_increasing else operator.le
indexer = np.where(op(left_distances, right_distances) |
(right_indexer == -1), left_indexer, right_indexer)
if tolerance is not None:
indexer = self._filter_indexer_tolerance(target, indexer,
tolerance)
return indexer |
Parameters ---------- keyarr: list - like Indexer to convert. | def _convert_listlike_indexer(self, keyarr, kind=None):
"""
Parameters
----------
keyarr : list-like
Indexer to convert.
Returns
-------
indexer : numpy.ndarray or None
Return an ndarray or None if cannot convert.
keyarr : numpy.ndarray
Return tuple-safe keys.
"""
if isinstance(keyarr, Index):
keyarr = self._convert_index_indexer(keyarr)
else:
keyarr = self._convert_arr_indexer(keyarr)
indexer = self._convert_list_indexer(keyarr, kind=kind)
return indexer, keyarr |
Consistent invalid indexer message. | def _invalid_indexer(self, form, key):
"""
Consistent invalid indexer message.
"""
raise TypeError("cannot do {form} indexing on {klass} with these "
"indexers [{key}] of {kind}".format(
form=form, klass=type(self), key=key,
kind=type(key))) |
Create index with target s values ( move/ add/ delete values as necessary ). | def reindex(self, target, method=None, level=None, limit=None,
tolerance=None):
"""
Create index with target's values (move/add/delete values
as necessary).
Parameters
----------
target : an iterable
Returns
-------
new_index : pd.Index
Resulting index.
indexer : np.ndarray or None
Indices of output values in original index.
"""
# GH6552: preserve names when reindexing to non-named target
# (i.e. neither Index nor Series).
preserve_names = not hasattr(target, 'name')
# GH7774: preserve dtype/tz if target is empty and not an Index.
target = _ensure_has_len(target) # target may be an iterator
if not isinstance(target, Index) and len(target) == 0:
attrs = self._get_attributes_dict()
attrs.pop('freq', None) # don't preserve freq
values = self._data[:0] # appropriately-dtyped empty array
target = self._simple_new(values, dtype=self.dtype, **attrs)
else:
target = ensure_index(target)
if level is not None:
if method is not None:
raise TypeError('Fill method not supported if level passed')
_, indexer, _ = self._join_level(target, level, how='right',
return_indexers=True)
else:
if self.equals(target):
indexer = None
else:
if self.is_unique:
indexer = self.get_indexer(target, method=method,
limit=limit,
tolerance=tolerance)
else:
if method is not None or limit is not None:
raise ValueError("cannot reindex a non-unique index "
"with a method or limit")
indexer, missing = self.get_indexer_non_unique(target)
if preserve_names and target.nlevels == 1 and target.name != self.name:
target = target.copy()
target.name = self.name
return target, indexer |
Create a new index with target s values ( move/ add/ delete values as necessary ) use with non - unique Index and a possibly non - unique target. | def _reindex_non_unique(self, target):
"""
Create a new index with target's values (move/add/delete values as
necessary) use with non-unique Index and a possibly non-unique target.
Parameters
----------
target : an iterable
Returns
-------
new_index : pd.Index
Resulting index.
indexer : np.ndarray or None
Indices of output values in original index.
"""
target = ensure_index(target)
indexer, missing = self.get_indexer_non_unique(target)
check = indexer != -1
new_labels = self.take(indexer[check])
new_indexer = None
if len(missing):
length = np.arange(len(indexer))
missing = ensure_platform_int(missing)
missing_labels = target.take(missing)
missing_indexer = ensure_int64(length[~check])
cur_labels = self.take(indexer[check]).values
cur_indexer = ensure_int64(length[check])
new_labels = np.empty(tuple([len(indexer)]), dtype=object)
new_labels[cur_indexer] = cur_labels
new_labels[missing_indexer] = missing_labels
# a unique indexer
if target.is_unique:
# see GH5553, make sure we use the right indexer
new_indexer = np.arange(len(indexer))
new_indexer[cur_indexer] = np.arange(len(cur_labels))
new_indexer[missing_indexer] = -1
# we have a non_unique selector, need to use the original
# indexer here
else:
# need to retake to have the same size as the indexer
indexer[~check] = -1
# reset the new indexer to account for the new size
new_indexer = np.arange(len(self.take(indexer)))
new_indexer[~check] = -1
new_index = self._shallow_copy_with_infer(new_labels, freq=None)
return new_index, indexer, new_indexer |
The join method * only * affects the level of the resulting MultiIndex. Otherwise it just exactly aligns the Index data to the labels of the level in the MultiIndex. | def _join_level(self, other, level, how='left', return_indexers=False,
keep_order=True):
"""
The join method *only* affects the level of the resulting
MultiIndex. Otherwise it just exactly aligns the Index data to the
labels of the level in the MultiIndex.
If ```keep_order == True```, the order of the data indexed by the
MultiIndex will not be changed; otherwise, it will tie out
with `other`.
"""
from .multi import MultiIndex
def _get_leaf_sorter(labels):
"""
Returns sorter for the inner most level while preserving the
order of higher levels.
"""
if labels[0].size == 0:
return np.empty(0, dtype='int64')
if len(labels) == 1:
lab = ensure_int64(labels[0])
sorter, _ = libalgos.groupsort_indexer(lab, 1 + lab.max())
return sorter
# find indexers of beginning of each set of
# same-key labels w.r.t all but last level
tic = labels[0][:-1] != labels[0][1:]
for lab in labels[1:-1]:
tic |= lab[:-1] != lab[1:]
starts = np.hstack(([True], tic, [True])).nonzero()[0]
lab = ensure_int64(labels[-1])
return lib.get_level_sorter(lab, ensure_int64(starts))
if isinstance(self, MultiIndex) and isinstance(other, MultiIndex):
raise TypeError('Join on level between two MultiIndex objects '
'is ambiguous')
left, right = self, other
flip_order = not isinstance(self, MultiIndex)
if flip_order:
left, right = right, left
how = {'right': 'left', 'left': 'right'}.get(how, how)
level = left._get_level_number(level)
old_level = left.levels[level]
if not right.is_unique:
raise NotImplementedError('Index._join_level on non-unique index '
'is not implemented')
new_level, left_lev_indexer, right_lev_indexer = \
old_level.join(right, how=how, return_indexers=True)
if left_lev_indexer is None:
if keep_order or len(left) == 0:
left_indexer = None
join_index = left
else: # sort the leaves
left_indexer = _get_leaf_sorter(left.codes[:level + 1])
join_index = left[left_indexer]
else:
left_lev_indexer = ensure_int64(left_lev_indexer)
rev_indexer = lib.get_reverse_indexer(left_lev_indexer,
len(old_level))
new_lev_codes = algos.take_nd(rev_indexer, left.codes[level],
allow_fill=False)
new_codes = list(left.codes)
new_codes[level] = new_lev_codes
new_levels = list(left.levels)
new_levels[level] = new_level
if keep_order: # just drop missing values. o.w. keep order
left_indexer = np.arange(len(left), dtype=np.intp)
mask = new_lev_codes != -1
if not mask.all():
new_codes = [lab[mask] for lab in new_codes]
left_indexer = left_indexer[mask]
else: # tie out the order with other
if level == 0: # outer most level, take the fast route
ngroups = 1 + new_lev_codes.max()
left_indexer, counts = libalgos.groupsort_indexer(
new_lev_codes, ngroups)
# missing values are placed first; drop them!
left_indexer = left_indexer[counts[0]:]
new_codes = [lab[left_indexer] for lab in new_codes]
else: # sort the leaves
mask = new_lev_codes != -1
mask_all = mask.all()
if not mask_all:
new_codes = [lab[mask] for lab in new_codes]
left_indexer = _get_leaf_sorter(new_codes[:level + 1])
new_codes = [lab[left_indexer] for lab in new_codes]
# left_indexers are w.r.t masked frame.
# reverse to original frame!
if not mask_all:
left_indexer = mask.nonzero()[0][left_indexer]
join_index = MultiIndex(levels=new_levels, codes=new_codes,
names=left.names, verify_integrity=False)
if right_lev_indexer is not None:
right_indexer = algos.take_nd(right_lev_indexer,
join_index.codes[level],
allow_fill=False)
else:
right_indexer = join_index.codes[level]
if flip_order:
left_indexer, right_indexer = right_indexer, left_indexer
if return_indexers:
left_indexer = (None if left_indexer is None
else ensure_platform_int(left_indexer))
right_indexer = (None if right_indexer is None
else ensure_platform_int(right_indexer))
return join_index, left_indexer, right_indexer
else:
return join_index |
Attempt to convert an array of data into an integer index. | def _try_convert_to_int_index(cls, data, copy, name, dtype):
"""
Attempt to convert an array of data into an integer index.
Parameters
----------
data : The data to convert.
copy : Whether to copy the data or not.
name : The name of the index returned.
Returns
-------
int_index : data converted to either an Int64Index or a
UInt64Index
Raises
------
ValueError if the conversion was not successful.
"""
from .numeric import Int64Index, UInt64Index
if not is_unsigned_integer_dtype(dtype):
# skip int64 conversion attempt if uint-like dtype is passed, as
# this could return Int64Index when UInt64Index is what's desrired
try:
res = data.astype('i8', copy=False)
if (res == data).all():
return Int64Index(res, copy=copy, name=name)
except (OverflowError, TypeError, ValueError):
pass
# Conversion to int64 failed (possibly due to overflow) or was skipped,
# so let's try now with uint64.
try:
res = data.astype('u8', copy=False)
if (res == data).all():
return UInt64Index(res, copy=copy, name=name)
except (OverflowError, TypeError, ValueError):
pass
raise ValueError |
Coerces data to ndarray. | def _coerce_to_ndarray(cls, data):
"""
Coerces data to ndarray.
Converts other iterables to list first and then to array.
Does not touch ndarrays.
Raises
------
TypeError
When the data passed in is a scalar.
"""
if not isinstance(data, (np.ndarray, Index)):
if data is None or is_scalar(data):
cls._scalar_data_error(data)
# other iterable of some kind
if not isinstance(data, (ABCSeries, list, tuple)):
data = list(data)
data = np.asarray(data)
return data |
We need to coerce a scalar to a compat for our index type. | def _coerce_scalar_to_index(self, item):
"""
We need to coerce a scalar to a compat for our index type.
Parameters
----------
item : scalar item to coerce
"""
dtype = self.dtype
if self._is_numeric_dtype and isna(item):
# We can't coerce to the numeric dtype of "self" (unless
# it's float) if there are NaN values in our output.
dtype = None
return Index([item], dtype=dtype, **self._get_attributes_dict()) |
Check value is valid for scalar op. | def _assert_can_do_op(self, value):
"""
Check value is valid for scalar op.
"""
if not is_scalar(value):
msg = "'value' must be a scalar, passed: {0}"
raise TypeError(msg.format(type(value).__name__)) |
Faster check for name in self when we know name is a Python identifier ( e. g. in NDFrame. __getattr__ which hits this to support. key lookup ). For indexes that can t hold identifiers ( everything but object & categorical ) we just return False. | def _can_hold_identifiers_and_holds_name(self, name):
"""
Faster check for ``name in self`` when we know `name` is a Python
identifier (e.g. in NDFrame.__getattr__, which hits this to support
. key lookup). For indexes that can't hold identifiers (everything
but object & categorical) we just return False.
https://github.com/pandas-dev/pandas/issues/19764
"""
if self.is_object() or self.is_categorical():
return name in self
return False |
Append a collection of Index options together. | def append(self, other):
"""
Append a collection of Index options together.
Parameters
----------
other : Index or list/tuple of indices
Returns
-------
appended : Index
"""
to_concat = [self]
if isinstance(other, (list, tuple)):
to_concat = to_concat + list(other)
else:
to_concat.append(other)
for obj in to_concat:
if not isinstance(obj, Index):
raise TypeError('all inputs must be Index')
names = {obj.name for obj in to_concat}
name = None if len(names) > 1 else self.name
return self._concat(to_concat, name) |
Return a new Index of the values set with the mask. | def putmask(self, mask, value):
"""
Return a new Index of the values set with the mask.
See Also
--------
numpy.ndarray.putmask
"""
values = self.values.copy()
try:
np.putmask(values, mask, self._convert_for_op(value))
return self._shallow_copy(values)
except (ValueError, TypeError) as err:
if is_object_dtype(self):
raise err
# coerces to object
return self.astype(object).putmask(mask, value) |
Determine if two Index objects contain the same elements. | def equals(self, other):
"""
Determine if two Index objects contain the same elements.
"""
if self.is_(other):
return True
if not isinstance(other, Index):
return False
if is_object_dtype(self) and not is_object_dtype(other):
# if other is not object, use other's logic for coercion
return other.equals(self)
try:
return array_equivalent(com.values_from_object(self),
com.values_from_object(other))
except Exception:
return False |
Similar to equals but check that other comparable attributes are also equal. | def identical(self, other):
"""
Similar to equals, but check that other comparable attributes are
also equal.
"""
return (self.equals(other) and
all((getattr(self, c, None) == getattr(other, c, None)
for c in self._comparables)) and
type(self) == type(other)) |
Return the label from the index or if not present the previous one. | def asof(self, label):
"""
Return the label from the index, or, if not present, the previous one.
Assuming that the index is sorted, return the passed index label if it
is in the index, or return the previous index label if the passed one
is not in the index.
Parameters
----------
label : object
The label up to which the method returns the latest index label.
Returns
-------
object
The passed label if it is in the index. The previous label if the
passed label is not in the sorted index or `NaN` if there is no
such label.
See Also
--------
Series.asof : Return the latest value in a Series up to the
passed index.
merge_asof : Perform an asof merge (similar to left join but it
matches on nearest key rather than equal key).
Index.get_loc : An `asof` is a thin wrapper around `get_loc`
with method='pad'.
Examples
--------
`Index.asof` returns the latest index label up to the passed label.
>>> idx = pd.Index(['2013-12-31', '2014-01-02', '2014-01-03'])
>>> idx.asof('2014-01-01')
'2013-12-31'
If the label is in the index, the method returns the passed label.
>>> idx.asof('2014-01-02')
'2014-01-02'
If all of the labels in the index are later than the passed label,
NaN is returned.
>>> idx.asof('1999-01-02')
nan
If the index is not sorted, an error is raised.
>>> idx_not_sorted = pd.Index(['2013-12-31', '2015-01-02',
... '2014-01-03'])
>>> idx_not_sorted.asof('2013-12-31')
Traceback (most recent call last):
ValueError: index must be monotonic increasing or decreasing
"""
try:
loc = self.get_loc(label, method='pad')
except KeyError:
return self._na_value
else:
if isinstance(loc, slice):
loc = loc.indices(len(self))[-1]
return self[loc] |
Find the locations ( indices ) of the labels from the index for every entry in the where argument. | def asof_locs(self, where, mask):
"""
Find the locations (indices) of the labels from the index for
every entry in the `where` argument.
As in the `asof` function, if the label (a particular entry in
`where`) is not in the index, the latest index label upto the
passed label is chosen and its index returned.
If all of the labels in the index are later than a label in `where`,
-1 is returned.
`mask` is used to ignore NA values in the index during calculation.
Parameters
----------
where : Index
An Index consisting of an array of timestamps.
mask : array-like
Array of booleans denoting where values in the original
data are not NA.
Returns
-------
numpy.ndarray
An array of locations (indices) of the labels from the Index
which correspond to the return values of the `asof` function
for every element in `where`.
"""
locs = self.values[mask].searchsorted(where.values, side='right')
locs = np.where(locs > 0, locs - 1, 0)
result = np.arange(len(self))[mask].take(locs)
first = mask.argmax()
result[(locs == 0) & (where.values < self.values[first])] = -1
return result |
Return a sorted copy of the index. | def sort_values(self, return_indexer=False, ascending=True):
"""
Return a sorted copy of the index.
Return a sorted copy of the index, and optionally return the indices
that sorted the index itself.
Parameters
----------
return_indexer : bool, default False
Should the indices that would sort the index be returned.
ascending : bool, default True
Should the index values be sorted in an ascending order.
Returns
-------
sorted_index : pandas.Index
Sorted copy of the index.
indexer : numpy.ndarray, optional
The indices that the index itself was sorted by.
See Also
--------
Series.sort_values : Sort values of a Series.
DataFrame.sort_values : Sort values in a DataFrame.
Examples
--------
>>> idx = pd.Index([10, 100, 1, 1000])
>>> idx
Int64Index([10, 100, 1, 1000], dtype='int64')
Sort values in ascending order (default behavior).
>>> idx.sort_values()
Int64Index([1, 10, 100, 1000], dtype='int64')
Sort values in descending order, and also get the indices `idx` was
sorted by.
>>> idx.sort_values(ascending=False, return_indexer=True)
(Int64Index([1000, 100, 10, 1], dtype='int64'), array([3, 1, 0, 2]))
"""
_as = self.argsort()
if not ascending:
_as = _as[::-1]
sorted_index = self.take(_as)
if return_indexer:
return sorted_index, _as
else:
return sorted_index |
Return the integer indices that would sort the index. | def argsort(self, *args, **kwargs):
"""
Return the integer indices that would sort the index.
Parameters
----------
*args
Passed to `numpy.ndarray.argsort`.
**kwargs
Passed to `numpy.ndarray.argsort`.
Returns
-------
numpy.ndarray
Integer indices that would sort the index if used as
an indexer.
See Also
--------
numpy.argsort : Similar method for NumPy arrays.
Index.sort_values : Return sorted copy of Index.
Examples
--------
>>> idx = pd.Index(['b', 'a', 'd', 'c'])
>>> idx
Index(['b', 'a', 'd', 'c'], dtype='object')
>>> order = idx.argsort()
>>> order
array([1, 0, 3, 2])
>>> idx[order]
Index(['a', 'b', 'c', 'd'], dtype='object')
"""
result = self.asi8
if result is None:
result = np.array(self)
return result.argsort(*args, **kwargs) |
Fast lookup of value from 1 - dimensional ndarray. Only use this if you know what you re doing. | def get_value(self, series, key):
"""
Fast lookup of value from 1-dimensional ndarray. Only use this if you
know what you're doing.
"""
# if we have something that is Index-like, then
# use this, e.g. DatetimeIndex
# Things like `Series._get_value` (via .at) pass the EA directly here.
s = getattr(series, '_values', series)
if isinstance(s, (ExtensionArray, Index)) and is_scalar(key):
# GH 20882, 21257
# Unify Index and ExtensionArray treatment
# First try to convert the key to a location
# If that fails, raise a KeyError if an integer
# index, otherwise, see if key is an integer, and
# try that
try:
iloc = self.get_loc(key)
return s[iloc]
except KeyError:
if (len(self) > 0 and
(self.holds_integer() or self.is_boolean())):
raise
elif is_integer(key):
return s[key]
s = com.values_from_object(series)
k = com.values_from_object(key)
k = self._convert_scalar_indexer(k, kind='getitem')
try:
return self._engine.get_value(s, k,
tz=getattr(series.dtype, 'tz', None))
except KeyError as e1:
if len(self) > 0 and (self.holds_integer() or self.is_boolean()):
raise
try:
return libindex.get_value_box(s, key)
except IndexError:
raise
except TypeError:
# generator/iterator-like
if is_iterator(key):
raise InvalidIndexError(key)
else:
raise e1
except Exception: # pragma: no cover
raise e1
except TypeError:
# python 3
if is_scalar(key): # pragma: no cover
raise IndexError(key)
raise InvalidIndexError(key) |
Fast lookup of value from 1 - dimensional ndarray. | def set_value(self, arr, key, value):
"""
Fast lookup of value from 1-dimensional ndarray.
Notes
-----
Only use this if you know what you're doing.
"""
self._engine.set_value(com.values_from_object(arr),
com.values_from_object(key), value) |
Guaranteed return of an indexer even when non - unique. | def get_indexer_for(self, target, **kwargs):
"""
Guaranteed return of an indexer even when non-unique.
This dispatches to get_indexer or get_indexer_nonunique
as appropriate.
"""
if self.is_unique:
return self.get_indexer(target, **kwargs)
indexer, _ = self.get_indexer_non_unique(target, **kwargs)
return indexer |
Group the index labels by a given array of values. | def groupby(self, values):
"""
Group the index labels by a given array of values.
Parameters
----------
values : array
Values used to determine the groups.
Returns
-------
groups : dict
{group name -> group labels}
"""
# TODO: if we are a MultiIndex, we can do better
# that converting to tuples
if isinstance(values, ABCMultiIndex):
values = values.values
values = ensure_categorical(values)
result = values._reverse_indexer()
# map to the label
result = {k: self.take(v) for k, v in result.items()}
return result |
Map values using input correspondence ( a dict Series or function ). | def map(self, mapper, na_action=None):
"""
Map values using input correspondence (a dict, Series, or function).
Parameters
----------
mapper : function, dict, or Series
Mapping correspondence.
na_action : {None, 'ignore'}
If 'ignore', propagate NA values, without passing them to the
mapping correspondence.
Returns
-------
applied : Union[Index, MultiIndex], inferred
The output of the mapping function applied to the index.
If the function returns a tuple with more than one element
a MultiIndex will be returned.
"""
from .multi import MultiIndex
new_values = super()._map_values(mapper, na_action=na_action)
attributes = self._get_attributes_dict()
# we can return a MultiIndex
if new_values.size and isinstance(new_values[0], tuple):
if isinstance(self, MultiIndex):
names = self.names
elif attributes.get('name'):
names = [attributes.get('name')] * len(new_values[0])
else:
names = None
return MultiIndex.from_tuples(new_values,
names=names)
attributes['copy'] = False
if not new_values.size:
# empty
attributes['dtype'] = self.dtype
return Index(new_values, **attributes) |
Return a boolean array where the index values are in values. | def isin(self, values, level=None):
"""
Return a boolean array where the index values are in `values`.
Compute boolean array of whether each index value is found in the
passed set of values. The length of the returned boolean array matches
the length of the index.
Parameters
----------
values : set or list-like
Sought values.
.. versionadded:: 0.18.1
Support for values as a set.
level : str or int, optional
Name or position of the index level to use (if the index is a
`MultiIndex`).
Returns
-------
is_contained : ndarray
NumPy array of boolean values.
See Also
--------
Series.isin : Same for Series.
DataFrame.isin : Same method for DataFrames.
Notes
-----
In the case of `MultiIndex` you must either specify `values` as a
list-like object containing tuples that are the same length as the
number of levels, or specify `level`. Otherwise it will raise a
``ValueError``.
If `level` is specified:
- if it is the name of one *and only one* index level, use that level;
- otherwise it should be a number indicating level position.
Examples
--------
>>> idx = pd.Index([1,2,3])
>>> idx
Int64Index([1, 2, 3], dtype='int64')
Check whether each index value in a list of values.
>>> idx.isin([1, 4])
array([ True, False, False])
>>> midx = pd.MultiIndex.from_arrays([[1,2,3],
... ['red', 'blue', 'green']],
... names=('number', 'color'))
>>> midx
MultiIndex(levels=[[1, 2, 3], ['blue', 'green', 'red']],
codes=[[0, 1, 2], [2, 0, 1]],
names=['number', 'color'])
Check whether the strings in the 'color' level of the MultiIndex
are in a list of colors.
>>> midx.isin(['red', 'orange', 'yellow'], level='color')
array([ True, False, False])
To check across the levels of a MultiIndex, pass a list of tuples:
>>> midx.isin([(1, 'red'), (3, 'red')])
array([ True, False, False])
For a DatetimeIndex, string values in `values` are converted to
Timestamps.
>>> dates = ['2000-03-11', '2000-03-12', '2000-03-13']
>>> dti = pd.to_datetime(dates)
>>> dti
DatetimeIndex(['2000-03-11', '2000-03-12', '2000-03-13'],
dtype='datetime64[ns]', freq=None)
>>> dti.isin(['2000-03-11'])
array([ True, False, False])
"""
if level is not None:
self._validate_index_level(level)
return algos.isin(self, values) |
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