laywerrobot/lib/python3.6/site-packages/gensim/models/word2vec_inner.pyx
2020-08-27 21:55:39 +02:00

993 lines
37 KiB
Cython
Executable file

#!/usr/bin/env cython
# cython: boundscheck=False
# cython: wraparound=False
# cython: cdivision=True
# cython: embedsignature=True
# coding: utf-8
#
# Copyright (C) 2013 Radim Rehurek <me@radimrehurek.com>
# Licensed under the GNU LGPL v2.1 - http://www.gnu.org/licenses/lgpl.html
"""Optimized cython functions for training :class:`~gensim.models.word2vec.Word2Vec` model."""
import cython
import numpy as np
cimport numpy as np
from libc.math cimport exp
from libc.math cimport log
from libc.string cimport memset
# scipy <= 0.15
try:
from scipy.linalg.blas import fblas
except ImportError:
# in scipy > 0.15, fblas function has been removed
import scipy.linalg.blas as fblas
REAL = np.float32
DEF MAX_SENTENCE_LEN = 10000
cdef scopy_ptr scopy=<scopy_ptr>PyCObject_AsVoidPtr(fblas.scopy._cpointer) # y = x
cdef saxpy_ptr saxpy=<saxpy_ptr>PyCObject_AsVoidPtr(fblas.saxpy._cpointer) # y += alpha * x
cdef sdot_ptr sdot=<sdot_ptr>PyCObject_AsVoidPtr(fblas.sdot._cpointer) # float = dot(x, y)
cdef dsdot_ptr dsdot=<dsdot_ptr>PyCObject_AsVoidPtr(fblas.sdot._cpointer) # double = dot(x, y)
cdef snrm2_ptr snrm2=<snrm2_ptr>PyCObject_AsVoidPtr(fblas.snrm2._cpointer) # sqrt(x^2)
cdef sscal_ptr sscal=<sscal_ptr>PyCObject_AsVoidPtr(fblas.sscal._cpointer) # x = alpha * x
DEF EXP_TABLE_SIZE = 1000
DEF MAX_EXP = 6
cdef REAL_t[EXP_TABLE_SIZE] EXP_TABLE
cdef REAL_t[EXP_TABLE_SIZE] LOG_TABLE
cdef int ONE = 1
cdef REAL_t ONEF = <REAL_t>1.0
# for when fblas.sdot returns a double
cdef REAL_t our_dot_double(const int *N, const float *X, const int *incX, const float *Y, const int *incY) nogil:
return <REAL_t>dsdot(N, X, incX, Y, incY)
# for when fblas.sdot returns a float
cdef REAL_t our_dot_float(const int *N, const float *X, const int *incX, const float *Y, const int *incY) nogil:
return <REAL_t>sdot(N, X, incX, Y, incY)
# for when no blas available
cdef REAL_t our_dot_noblas(const int *N, const float *X, const int *incX, const float *Y, const int *incY) nogil:
# not a true full dot()-implementation: just enough for our cases
cdef int i
cdef REAL_t a
a = <REAL_t>0.0
for i from 0 <= i < N[0] by 1:
a += X[i] * Y[i]
return a
# for when no blas available
cdef void our_saxpy_noblas(const int *N, const float *alpha, const float *X, const int *incX, float *Y, const int *incY) nogil:
cdef int i
for i from 0 <= i < N[0] by 1:
Y[i * (incY[0])] = (alpha[0]) * X[i * (incX[0])] + Y[i * (incY[0])]
cdef void fast_sentence_sg_hs(
const np.uint32_t *word_point, const np.uint8_t *word_code, const int codelen,
REAL_t *syn0, REAL_t *syn1, const int size,
const np.uint32_t word2_index, const REAL_t alpha, REAL_t *work, REAL_t *word_locks,
const int _compute_loss, REAL_t *_running_training_loss_param) nogil:
"""Train on a single effective word from the current batch, using the Skip-Gram model.
In this model we are using a given word to predict a context word (a word that is
close to the one we are using as training). Hierarchical softmax is used to speed-up
training.
Parameters
----------
word_point
Vector representation of the current word.
word_code
ASCII (char == uint8) representation of the current word.
codelen
Number of characters (length) in the current word.
syn0
Embeddings for the words in the vocabulary (`model.wv.vectors`)
syn1
Weights of the hidden layer in the model's trainable neural network.
size
Length of the embeddings.
word2_index
Index of the context word in the vocabulary.
alpha
Learning rate.
work
Private working memory for each worker.
word_locks
Lock factors for each word. A value of 0 will block training.
_compute_loss
Whether or not the loss should be computed at this step.
_running_training_loss_param
Running loss, used to debug or inspect how training progresses.
"""
cdef long long a, b
cdef long long row1 = word2_index * size, row2, sgn
cdef REAL_t f, g, f_dot, lprob
memset(work, 0, size * cython.sizeof(REAL_t))
for b in range(codelen):
row2 = word_point[b] * size
f_dot = our_dot(&size, &syn0[row1], &ONE, &syn1[row2], &ONE)
if f_dot <= -MAX_EXP or f_dot >= MAX_EXP:
continue
f = EXP_TABLE[<int>((f_dot + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
g = (1 - word_code[b] - f) * alpha
if _compute_loss == 1:
sgn = (-1)**word_code[b] # ch function: 0-> 1, 1 -> -1
lprob = -1*sgn*f_dot
if lprob <= -MAX_EXP or lprob >= MAX_EXP:
continue
lprob = LOG_TABLE[<int>((lprob + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
_running_training_loss_param[0] = _running_training_loss_param[0] - lprob
our_saxpy(&size, &g, &syn1[row2], &ONE, work, &ONE)
our_saxpy(&size, &g, &syn0[row1], &ONE, &syn1[row2], &ONE)
our_saxpy(&size, &word_locks[word2_index], work, &ONE, &syn0[row1], &ONE)
# to support random draws from negative-sampling cum_table
cdef inline unsigned long long bisect_left(np.uint32_t *a, unsigned long long x, unsigned long long lo, unsigned long long hi) nogil:
cdef unsigned long long mid
while hi > lo:
mid = (lo + hi) >> 1
if a[mid] >= x:
hi = mid
else:
lo = mid + 1
return lo
# this quick & dirty RNG apparently matches Java's (non-Secure)Random
# note this function side-effects next_random to set up the next number
cdef inline unsigned long long random_int32(unsigned long long *next_random) nogil:
cdef unsigned long long this_random = next_random[0] >> 16
next_random[0] = (next_random[0] * <unsigned long long>25214903917ULL + 11) & 281474976710655ULL
return this_random
cdef unsigned long long fast_sentence_sg_neg(
const int negative, np.uint32_t *cum_table, unsigned long long cum_table_len,
REAL_t *syn0, REAL_t *syn1neg, const int size, const np.uint32_t word_index,
const np.uint32_t word2_index, const REAL_t alpha, REAL_t *work,
unsigned long long next_random, REAL_t *word_locks,
const int _compute_loss, REAL_t *_running_training_loss_param) nogil:
"""Train on a single effective word from the current batch, using the Skip-Gram model.
In this model we are using a given word to predict a context word (a word that is
close to the one we are using as training). Negative sampling is used to speed-up
training.
Parameters
----------
negative
Number of negative words to be sampled.
cum_table
Cumulative-distribution table using stored vocabulary word counts for
drawing random words (with a negative label).
cum_table_len
Length of the `cum_table`
syn0
Embeddings for the words in the vocabulary (`model.wv.vectors`)
syn1neg
Weights of the hidden layer in the model's trainable neural network.
size
Length of the embeddings.
word_index
Index of the current training word in the vocabulary.
word2_index
Index of the context word in the vocabulary.
alpha
Learning rate.
work
Private working memory for each worker.
next_random
Seed to produce the index for the next word to be randomly sampled.
word_locks
Lock factors for each word. A value of 0 will block training.
_compute_loss
Whether or not the loss should be computed at this step.
_running_training_loss_param
Running loss, used to debug or inspect how training progresses.
Returns
-------
Seed to draw the training word for the next iteration of the same routine.
"""
cdef long long a
cdef long long row1 = word2_index * size, row2
cdef unsigned long long modulo = 281474976710655ULL
cdef REAL_t f, g, label, f_dot, log_e_f_dot
cdef np.uint32_t target_index
cdef int d
memset(work, 0, size * cython.sizeof(REAL_t))
for d in range(negative+1):
if d == 0:
target_index = word_index
label = ONEF
else:
target_index = bisect_left(cum_table, (next_random >> 16) % cum_table[cum_table_len-1], 0, cum_table_len)
next_random = (next_random * <unsigned long long>25214903917ULL + 11) & modulo
if target_index == word_index:
continue
label = <REAL_t>0.0
row2 = target_index * size
f_dot = our_dot(&size, &syn0[row1], &ONE, &syn1neg[row2], &ONE)
if f_dot <= -MAX_EXP or f_dot >= MAX_EXP:
continue
f = EXP_TABLE[<int>((f_dot + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
g = (label - f) * alpha
if _compute_loss == 1:
f_dot = (f_dot if d == 0 else -f_dot)
if f_dot <= -MAX_EXP or f_dot >= MAX_EXP:
continue
log_e_f_dot = LOG_TABLE[<int>((f_dot + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
_running_training_loss_param[0] = _running_training_loss_param[0] - log_e_f_dot
our_saxpy(&size, &g, &syn1neg[row2], &ONE, work, &ONE)
our_saxpy(&size, &g, &syn0[row1], &ONE, &syn1neg[row2], &ONE)
our_saxpy(&size, &word_locks[word2_index], work, &ONE, &syn0[row1], &ONE)
return next_random
cdef void fast_sentence_cbow_hs(
const np.uint32_t *word_point, const np.uint8_t *word_code, int codelens[MAX_SENTENCE_LEN],
REAL_t *neu1, REAL_t *syn0, REAL_t *syn1, const int size,
const np.uint32_t indexes[MAX_SENTENCE_LEN], const REAL_t alpha, REAL_t *work,
int i, int j, int k, int cbow_mean, REAL_t *word_locks,
const int _compute_loss, REAL_t *_running_training_loss_param) nogil:
"""Train on a single effective word from the current batch, using the CBOW method.
Using this method we train the trainable neural network by attempting to predict a
given word by its context (words surrounding the one we are trying to predict).
Hierarchical softmax method is used to speed-up training.
Parameters
----------
word_point
Vector representation of the current word.
word_code
ASCII (char == uint8) representation of the current word.
codelens
Number of characters (length) for all words in the context.
neu1
Private working memory for every worker.
syn0
Embeddings for the words in the vocabulary (`model.wv.vectors`)
syn1
Weights of the hidden layer in the model's trainable neural network.
size
Length of the embeddings.
word2_index
Index of the context word in the vocabulary.
alpha
Learning rate.
work
Private working memory for each worker.
i
Index of the word to be predicted from the context.
j
Index of the word at the beginning of the context window.
k
Index of the word at the end of the context window.
cbow_mean
If 0, use the sum of the context word vectors as the prediction. If 1, use the mean.
word_locks
Lock factors for each word. A value of 0 will block training.
_compute_loss
Whether or not the loss should be computed at this step.
_running_training_loss_param
Running loss, used to debug or inspect how training progresses.
"""
cdef long long a, b
cdef long long row2, sgn
cdef REAL_t f, g, count, inv_count = 1.0, f_dot, lprob
cdef int m
memset(neu1, 0, size * cython.sizeof(REAL_t))
count = <REAL_t>0.0
for m in range(j, k):
if m == i:
continue
else:
count += ONEF
our_saxpy(&size, &ONEF, &syn0[indexes[m] * size], &ONE, neu1, &ONE)
if count > (<REAL_t>0.5):
inv_count = ONEF/count
if cbow_mean:
sscal(&size, &inv_count, neu1, &ONE) # (does this need BLAS-variants like saxpy?)
memset(work, 0, size * cython.sizeof(REAL_t))
for b in range(codelens[i]):
row2 = word_point[b] * size
f_dot = our_dot(&size, neu1, &ONE, &syn1[row2], &ONE)
if f_dot <= -MAX_EXP or f_dot >= MAX_EXP:
continue
f = EXP_TABLE[<int>((f_dot + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
g = (1 - word_code[b] - f) * alpha
if _compute_loss == 1:
sgn = (-1)**word_code[b] # ch function: 0-> 1, 1 -> -1
lprob = -1*sgn*f_dot
if lprob <= -MAX_EXP or lprob >= MAX_EXP:
continue
lprob = LOG_TABLE[<int>((lprob + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
_running_training_loss_param[0] = _running_training_loss_param[0] - lprob
our_saxpy(&size, &g, &syn1[row2], &ONE, work, &ONE)
our_saxpy(&size, &g, neu1, &ONE, &syn1[row2], &ONE)
if not cbow_mean: # divide error over summed window vectors
sscal(&size, &inv_count, work, &ONE) # (does this need BLAS-variants like saxpy?)
for m in range(j, k):
if m == i:
continue
else:
our_saxpy(&size, &word_locks[indexes[m]], work, &ONE, &syn0[indexes[m] * size], &ONE)
cdef unsigned long long fast_sentence_cbow_neg(
const int negative, np.uint32_t *cum_table, unsigned long long cum_table_len, int codelens[MAX_SENTENCE_LEN],
REAL_t *neu1, REAL_t *syn0, REAL_t *syn1neg, const int size,
const np.uint32_t indexes[MAX_SENTENCE_LEN], const REAL_t alpha, REAL_t *work,
int i, int j, int k, int cbow_mean, unsigned long long next_random, REAL_t *word_locks,
const int _compute_loss, REAL_t *_running_training_loss_param) nogil:
"""Train on a single effective word from the current batch, using the CBOW method.
Using this method we train the trainable neural network by attempting to predict a
given word by its context (words surrounding the one we are trying to predict).
Negative sampling is used to speed-up training.
Parameters
----------
negative
Number of negative words to be sampled.
cum_table
Cumulative-distribution table using stored vocabulary word counts for
drawing random words (with a negative label).
cum_table_len
Length of the `cum_table`
codelens
Number of characters (length) for all words in the context.
neu1
Private working memory for every worker.
syn0
Embeddings for the words in the vocabulary (`model.wv.vectors`)
syn1neg
Weights of the hidden layer in the model's trainable neural network.
size
Length of the embeddings.
indexes
Indexes of the context words in the vocabulary.
alpha
Learning rate.
work
Private working memory for each worker.
i
Index of the word to be predicted from the context.
j
Index of the word at the beginning of the context window.
k
Index of the word at the end of the context window.
cbow_mean
If 0, use the sum of the context word vectors as the prediction. If 1, use the mean.
next_random
Seed for the drawing the predicted word for the next iteration of the same routine.
word_locks
Lock factors for each word. A value of 0 will block training.
_compute_loss
Whether or not the loss should be computed at this step.
_running_training_loss_param
Running loss, used to debug or inspect how training progresses.
"""
cdef long long a
cdef long long row2
cdef unsigned long long modulo = 281474976710655ULL
cdef REAL_t f, g, count, inv_count = 1.0, label, log_e_f_dot, f_dot
cdef np.uint32_t target_index, word_index
cdef int d, m
word_index = indexes[i]
memset(neu1, 0, size * cython.sizeof(REAL_t))
count = <REAL_t>0.0
for m in range(j, k):
if m == i:
continue
else:
count += ONEF
our_saxpy(&size, &ONEF, &syn0[indexes[m] * size], &ONE, neu1, &ONE)
if count > (<REAL_t>0.5):
inv_count = ONEF/count
if cbow_mean:
sscal(&size, &inv_count, neu1, &ONE) # (does this need BLAS-variants like saxpy?)
memset(work, 0, size * cython.sizeof(REAL_t))
for d in range(negative+1):
if d == 0:
target_index = word_index
label = ONEF
else:
target_index = bisect_left(cum_table, (next_random >> 16) % cum_table[cum_table_len-1], 0, cum_table_len)
next_random = (next_random * <unsigned long long>25214903917ULL + 11) & modulo
if target_index == word_index:
continue
label = <REAL_t>0.0
row2 = target_index * size
f_dot = our_dot(&size, neu1, &ONE, &syn1neg[row2], &ONE)
if f_dot <= -MAX_EXP or f_dot >= MAX_EXP:
continue
f = EXP_TABLE[<int>((f_dot + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
g = (label - f) * alpha
if _compute_loss == 1:
f_dot = (f_dot if d == 0 else -f_dot)
if f_dot <= -MAX_EXP or f_dot >= MAX_EXP:
continue
log_e_f_dot = LOG_TABLE[<int>((f_dot + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
_running_training_loss_param[0] = _running_training_loss_param[0] - log_e_f_dot
our_saxpy(&size, &g, &syn1neg[row2], &ONE, work, &ONE)
our_saxpy(&size, &g, neu1, &ONE, &syn1neg[row2], &ONE)
if not cbow_mean: # divide error over summed window vectors
sscal(&size, &inv_count, work, &ONE) # (does this need BLAS-variants like saxpy?)
for m in range(j,k):
if m == i:
continue
else:
our_saxpy(&size, &word_locks[indexes[m]], work, &ONE, &syn0[indexes[m]*size], &ONE)
return next_random
def train_batch_sg(model, sentences, alpha, _work, compute_loss):
"""Update skip-gram model by training on a batch of sentences.
Called internally from :meth:`~gensim.models.word2vec.Word2Vec.train`.
Parameters
----------
model : :class:`~gensim.models.word2Vec.Word2Vec`
The Word2Vec model instance to train.
sentences : iterable of list of str
The corpus used to train the model.
alpha : float
The learning rate
_work : np.ndarray
Private working memory for each worker.
compute_loss : bool
Whether or not the training loss should be computed in this batch.
Returns
-------
int
Number of words in the vocabulary actually used for training (They already existed in the vocabulary
and were not discarded by negative sampling).
"""
cdef int hs = model.hs
cdef int negative = model.negative
cdef int sample = (model.vocabulary.sample != 0)
cdef int _compute_loss = (1 if compute_loss else 0)
cdef REAL_t _running_training_loss = model.running_training_loss
cdef REAL_t *syn0 = <REAL_t *>(np.PyArray_DATA(model.wv.vectors))
cdef REAL_t *word_locks = <REAL_t *>(np.PyArray_DATA(model.trainables.vectors_lockf))
cdef REAL_t *work
cdef REAL_t _alpha = alpha
cdef int size = model.wv.vector_size
cdef int codelens[MAX_SENTENCE_LEN]
cdef np.uint32_t indexes[MAX_SENTENCE_LEN]
cdef np.uint32_t reduced_windows[MAX_SENTENCE_LEN]
cdef int sentence_idx[MAX_SENTENCE_LEN + 1]
cdef int window = model.window
cdef int i, j, k
cdef int effective_words = 0, effective_sentences = 0
cdef int sent_idx, idx_start, idx_end
# For hierarchical softmax
cdef REAL_t *syn1
cdef np.uint32_t *points[MAX_SENTENCE_LEN]
cdef np.uint8_t *codes[MAX_SENTENCE_LEN]
# For negative sampling
cdef REAL_t *syn1neg
cdef np.uint32_t *cum_table
cdef unsigned long long cum_table_len
# for sampling (negative and frequent-word downsampling)
cdef unsigned long long next_random
if hs:
syn1 = <REAL_t *>(np.PyArray_DATA(model.trainables.syn1))
if negative:
syn1neg = <REAL_t *>(np.PyArray_DATA(model.trainables.syn1neg))
cum_table = <np.uint32_t *>(np.PyArray_DATA(model.vocabulary.cum_table))
cum_table_len = len(model.vocabulary.cum_table)
if negative or sample:
next_random = (2**24) * model.random.randint(0, 2**24) + model.random.randint(0, 2**24)
# convert Python structures to primitive types, so we can release the GIL
work = <REAL_t *>np.PyArray_DATA(_work)
# prepare C structures so we can go "full C" and release the Python GIL
vlookup = model.wv.vocab
sentence_idx[0] = 0 # indices of the first sentence always start at 0
for sent in sentences:
if not sent:
continue # ignore empty sentences; leave effective_sentences unchanged
for token in sent:
word = vlookup[token] if token in vlookup else None
if word is None:
continue # leaving `effective_words` unchanged = shortening the sentence = expanding the window
if sample and word.sample_int < random_int32(&next_random):
continue
indexes[effective_words] = word.index
if hs:
codelens[effective_words] = <int>len(word.code)
codes[effective_words] = <np.uint8_t *>np.PyArray_DATA(word.code)
points[effective_words] = <np.uint32_t *>np.PyArray_DATA(word.point)
effective_words += 1
if effective_words == MAX_SENTENCE_LEN:
break # TODO: log warning, tally overflow?
# keep track of which words go into which sentence, so we don't train
# across sentence boundaries.
# indices of sentence number X are between <sentence_idx[X], sentence_idx[X])
effective_sentences += 1
sentence_idx[effective_sentences] = effective_words
if effective_words == MAX_SENTENCE_LEN:
break # TODO: log warning, tally overflow?
# precompute "reduced window" offsets in a single randint() call
for i, item in enumerate(model.random.randint(0, window, effective_words)):
reduced_windows[i] = item
# release GIL & train on all sentences
with nogil:
for sent_idx in range(effective_sentences):
idx_start = sentence_idx[sent_idx]
idx_end = sentence_idx[sent_idx + 1]
for i in range(idx_start, idx_end):
j = i - window + reduced_windows[i]
if j < idx_start:
j = idx_start
k = i + window + 1 - reduced_windows[i]
if k > idx_end:
k = idx_end
for j in range(j, k):
if j == i:
continue
if hs:
fast_sentence_sg_hs(points[i], codes[i], codelens[i], syn0, syn1, size, indexes[j], _alpha, work, word_locks, _compute_loss, &_running_training_loss)
if negative:
next_random = fast_sentence_sg_neg(negative, cum_table, cum_table_len, syn0, syn1neg, size, indexes[i], indexes[j], _alpha, work, next_random, word_locks, _compute_loss, &_running_training_loss)
model.running_training_loss = _running_training_loss
return effective_words
def train_batch_cbow(model, sentences, alpha, _work, _neu1, compute_loss):
"""Update CBOW model by training on a batch of sentences.
Called internally from :meth:`~gensim.models.word2vec.Word2Vec.train`.
Parameters
----------
model : :class:`~gensim.models.word2vec.Word2Vec`
The Word2Vec model instance to train.
sentences : iterable of list of str
The corpus used to train the model.
alpha : float
The learning rate.
_work : np.ndarray
Private working memory for each worker.
_neu1 : np.ndarray
Private working memory for each worker.
compute_loss : bool
Whether or not the training loss should be computed in this batch.
Returns
-------
int
Number of words in the vocabulary actually used for training (They already existed in the vocabulary
and were not discarded by negative sampling).
"""
cdef int hs = model.hs
cdef int negative = model.negative
cdef int sample = (model.vocabulary.sample != 0)
cdef int cbow_mean = model.cbow_mean
cdef int _compute_loss = (1 if compute_loss == True else 0)
cdef REAL_t _running_training_loss = model.running_training_loss
cdef REAL_t *syn0 = <REAL_t *>(np.PyArray_DATA(model.wv.vectors))
cdef REAL_t *word_locks = <REAL_t *>(np.PyArray_DATA(model.trainables.vectors_lockf))
cdef REAL_t *work
cdef REAL_t _alpha = alpha
cdef int size = model.wv.vector_size
cdef int codelens[MAX_SENTENCE_LEN]
cdef np.uint32_t indexes[MAX_SENTENCE_LEN]
cdef np.uint32_t reduced_windows[MAX_SENTENCE_LEN]
cdef int sentence_idx[MAX_SENTENCE_LEN + 1]
cdef int window = model.window
cdef int i, j, k
cdef int effective_words = 0, effective_sentences = 0
cdef int sent_idx, idx_start, idx_end
# For hierarchical softmax
cdef REAL_t *syn1
cdef np.uint32_t *points[MAX_SENTENCE_LEN]
cdef np.uint8_t *codes[MAX_SENTENCE_LEN]
# For negative sampling
cdef REAL_t *syn1neg
cdef np.uint32_t *cum_table
cdef unsigned long long cum_table_len
# for sampling (negative and frequent-word downsampling)
cdef unsigned long long next_random
if hs:
syn1 = <REAL_t *>(np.PyArray_DATA(model.trainables.syn1))
if negative:
syn1neg = <REAL_t *>(np.PyArray_DATA(model.trainables.syn1neg))
cum_table = <np.uint32_t *>(np.PyArray_DATA(model.vocabulary.cum_table))
cum_table_len = len(model.vocabulary.cum_table)
if negative or sample:
next_random = (2**24) * model.random.randint(0, 2**24) + model.random.randint(0, 2**24)
# convert Python structures to primitive types, so we can release the GIL
work = <REAL_t *>np.PyArray_DATA(_work)
neu1 = <REAL_t *>np.PyArray_DATA(_neu1)
# prepare C structures so we can go "full C" and release the Python GIL
vlookup = model.wv.vocab
sentence_idx[0] = 0 # indices of the first sentence always start at 0
for sent in sentences:
if not sent:
continue # ignore empty sentences; leave effective_sentences unchanged
for token in sent:
word = vlookup[token] if token in vlookup else None
if word is None:
continue # leaving `effective_words` unchanged = shortening the sentence = expanding the window
if sample and word.sample_int < random_int32(&next_random):
continue
indexes[effective_words] = word.index
if hs:
codelens[effective_words] = <int>len(word.code)
codes[effective_words] = <np.uint8_t *>np.PyArray_DATA(word.code)
points[effective_words] = <np.uint32_t *>np.PyArray_DATA(word.point)
effective_words += 1
if effective_words == MAX_SENTENCE_LEN:
break # TODO: log warning, tally overflow?
# keep track of which words go into which sentence, so we don't train
# across sentence boundaries.
# indices of sentence number X are between <sentence_idx[X], sentence_idx[X])
effective_sentences += 1
sentence_idx[effective_sentences] = effective_words
if effective_words == MAX_SENTENCE_LEN:
break # TODO: log warning, tally overflow?
# precompute "reduced window" offsets in a single randint() call
for i, item in enumerate(model.random.randint(0, window, effective_words)):
reduced_windows[i] = item
# release GIL & train on all sentences
with nogil:
for sent_idx in range(effective_sentences):
idx_start = sentence_idx[sent_idx]
idx_end = sentence_idx[sent_idx + 1]
for i in range(idx_start, idx_end):
j = i - window + reduced_windows[i]
if j < idx_start:
j = idx_start
k = i + window + 1 - reduced_windows[i]
if k > idx_end:
k = idx_end
if hs:
fast_sentence_cbow_hs(points[i], codes[i], codelens, neu1, syn0, syn1, size, indexes, _alpha, work, i, j, k, cbow_mean, word_locks, _compute_loss, &_running_training_loss)
if negative:
next_random = fast_sentence_cbow_neg(negative, cum_table, cum_table_len, codelens, neu1, syn0, syn1neg, size, indexes, _alpha, work, i, j, k, cbow_mean, next_random, word_locks, _compute_loss, &_running_training_loss)
model.running_training_loss = _running_training_loss
return effective_words
def score_sentence_sg(model, sentence, _work):
"""Obtain likelihood score for a single sentence in a fitted skip-gram representation.
Notes
-----
This scoring function is only implemented for hierarchical softmax (`model.hs == 1`).
The model should have been trained using the skip-gram model (`model.sg` == 1`).
Parameters
----------
model : :class:`~gensim.models.word2vec.Word2Vec`
The trained model. It **MUST** have been trained using hierarchical softmax and the skip-gram algorithm.
sentence : list of str
The words comprising the sentence to be scored.
_work : np.ndarray
Private working memory for each worker.
Returns
-------
float
The probability assigned to this sentence by the Skip-Gram model.
"""
cdef REAL_t *syn0 = <REAL_t *>(np.PyArray_DATA(model.wv.vectors))
cdef REAL_t *work
cdef int size = model.wv.vector_size
cdef int codelens[MAX_SENTENCE_LEN]
cdef np.uint32_t indexes[MAX_SENTENCE_LEN]
cdef int sentence_len
cdef int window = model.window
cdef int i, j, k
cdef long result = 0
cdef REAL_t *syn1
cdef np.uint32_t *points[MAX_SENTENCE_LEN]
cdef np.uint8_t *codes[MAX_SENTENCE_LEN]
syn1 = <REAL_t *>(np.PyArray_DATA(model.trainables.syn1))
# convert Python structures to primitive types, so we can release the GIL
work = <REAL_t *>np.PyArray_DATA(_work)
vlookup = model.wv.vocab
i = 0
for token in sentence:
word = vlookup[token] if token in vlookup else None
if word is None:
continue # should drop the
indexes[i] = word.index
codelens[i] = <int>len(word.code)
codes[i] = <np.uint8_t *>np.PyArray_DATA(word.code)
points[i] = <np.uint32_t *>np.PyArray_DATA(word.point)
result += 1
i += 1
if i == MAX_SENTENCE_LEN:
break # TODO: log warning, tally overflow?
sentence_len = i
# release GIL & train on the sentence
work[0] = 0.0
with nogil:
for i in range(sentence_len):
if codelens[i] == 0:
continue
j = i - window
if j < 0:
j = 0
k = i + window + 1
if k > sentence_len:
k = sentence_len
for j in range(j, k):
if j == i or codelens[j] == 0:
continue
score_pair_sg_hs(points[i], codes[i], codelens[i], syn0, syn1, size, indexes[j], work)
return work[0]
cdef void score_pair_sg_hs(
const np.uint32_t *word_point, const np.uint8_t *word_code, const int codelen,
REAL_t *syn0, REAL_t *syn1, const int size,
const np.uint32_t word2_index, REAL_t *work) nogil:
cdef long long b
cdef long long row1 = word2_index * size, row2, sgn
cdef REAL_t f
for b in range(codelen):
row2 = word_point[b] * size
f = our_dot(&size, &syn0[row1], &ONE, &syn1[row2], &ONE)
sgn = (-1)**word_code[b] # ch function: 0-> 1, 1 -> -1
f *= sgn
if f <= -MAX_EXP or f >= MAX_EXP:
continue
f = LOG_TABLE[<int>((f + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
work[0] += f
def score_sentence_cbow(model, sentence, _work, _neu1):
"""Obtain likelihood score for a single sentence in a fitted CBOW representation.
Notes
-----
This scoring function is only implemented for hierarchical softmax (`model.hs == 1`).
The model should have been trained using the skip-gram model (`model.cbow` == 1`).
Parameters
----------
model : :class:`~gensim.models.word2vec.Word2Vec`
The trained model. It **MUST** have been trained using hierarchical softmax and the CBOW algorithm.
sentence : list of str
The words comprising the sentence to be scored.
_work : np.ndarray
Private working memory for each worker.
_neu1 : np.ndarray
Private working memory for each worker.
Returns
-------
float
The probability assigned to this sentence by the Skip-Gram model.
"""
cdef int cbow_mean = model.cbow_mean
cdef REAL_t *syn0 = <REAL_t *>(np.PyArray_DATA(model.wv.vectors))
cdef REAL_t *work
cdef REAL_t *neu1
cdef int size = model.wv.vector_size
cdef int codelens[MAX_SENTENCE_LEN]
cdef np.uint32_t indexes[MAX_SENTENCE_LEN]
cdef int sentence_len
cdef int window = model.window
cdef int i, j, k
cdef long result = 0
# For hierarchical softmax
cdef REAL_t *syn1
cdef np.uint32_t *points[MAX_SENTENCE_LEN]
cdef np.uint8_t *codes[MAX_SENTENCE_LEN]
syn1 = <REAL_t *>(np.PyArray_DATA(model.trainables.syn1))
# convert Python structures to primitive types, so we can release the GIL
work = <REAL_t *>np.PyArray_DATA(_work)
neu1 = <REAL_t *>np.PyArray_DATA(_neu1)
vlookup = model.wv.vocab
i = 0
for token in sentence:
word = vlookup[token] if token in vlookup else None
if word is None:
continue # for score, should this be a default negative value?
indexes[i] = word.index
codelens[i] = <int>len(word.code)
codes[i] = <np.uint8_t *>np.PyArray_DATA(word.code)
points[i] = <np.uint32_t *>np.PyArray_DATA(word.point)
result += 1
i += 1
if i == MAX_SENTENCE_LEN:
break # TODO: log warning, tally overflow?
sentence_len = i
# release GIL & train on the sentence
work[0] = 0.0
with nogil:
for i in range(sentence_len):
if codelens[i] == 0:
continue
j = i - window
if j < 0:
j = 0
k = i + window + 1
if k > sentence_len:
k = sentence_len
score_pair_cbow_hs(points[i], codes[i], codelens, neu1, syn0, syn1, size, indexes, work, i, j, k, cbow_mean)
return work[0]
cdef void score_pair_cbow_hs(
const np.uint32_t *word_point, const np.uint8_t *word_code, int codelens[MAX_SENTENCE_LEN],
REAL_t *neu1, REAL_t *syn0, REAL_t *syn1, const int size,
const np.uint32_t indexes[MAX_SENTENCE_LEN], REAL_t *work,
int i, int j, int k, int cbow_mean) nogil:
cdef long long a, b
cdef long long row2
cdef REAL_t f, g, count, inv_count, sgn
cdef int m
memset(neu1, 0, size * cython.sizeof(REAL_t))
count = <REAL_t>0.0
for m in range(j, k):
if m == i or codelens[m] == 0:
continue
else:
count += ONEF
our_saxpy(&size, &ONEF, &syn0[indexes[m] * size], &ONE, neu1, &ONE)
if count > (<REAL_t>0.5):
inv_count = ONEF/count
if cbow_mean:
sscal(&size, &inv_count, neu1, &ONE)
for b in range(codelens[i]):
row2 = word_point[b] * size
f = our_dot(&size, neu1, &ONE, &syn1[row2], &ONE)
sgn = (-1)**word_code[b] # ch function: 0-> 1, 1 -> -1
f *= sgn
if f <= -MAX_EXP or f >= MAX_EXP:
continue
f = LOG_TABLE[<int>((f + MAX_EXP) * (EXP_TABLE_SIZE / MAX_EXP / 2))]
work[0] += f
def init():
"""Precompute function `sigmoid(x) = 1 / (1 + exp(-x))`, for x values discretized into table EXP_TABLE.
Also calculate log(sigmoid(x)) into LOG_TABLE.
Returns
-------
{0, 1, 2}
Enumeration to signify underlying data type returned by the BLAS dot product calculation.
0 signifies double, 1 signifies double, and 2 signifies that custom cython loops were used
instead of BLAS.
"""
global our_dot
global our_saxpy
cdef int i
cdef float *x = [<float>10.0]
cdef float *y = [<float>0.01]
cdef float expected = <float>0.1
cdef int size = 1
cdef double d_res
cdef float *p_res
# build the sigmoid table
for i in range(EXP_TABLE_SIZE):
EXP_TABLE[i] = <REAL_t>exp((i / <REAL_t>EXP_TABLE_SIZE * 2 - 1) * MAX_EXP)
EXP_TABLE[i] = <REAL_t>(EXP_TABLE[i] / (EXP_TABLE[i] + 1))
LOG_TABLE[i] = <REAL_t>log( EXP_TABLE[i] )
# check whether sdot returns double or float
d_res = dsdot(&size, x, &ONE, y, &ONE)
p_res = <float *>&d_res
if abs(d_res - expected) < 0.0001:
our_dot = our_dot_double
our_saxpy = saxpy
return 0 # double
elif abs(p_res[0] - expected) < 0.0001:
our_dot = our_dot_float
our_saxpy = saxpy
return 1 # float
else:
# neither => use cython loops, no BLAS
# actually, the BLAS is so messed up we'll probably have segfaulted above and never even reach here
our_dot = our_dot_noblas
our_saxpy = our_saxpy_noblas
return 2
FAST_VERSION = init() # initialize the module
MAX_WORDS_IN_BATCH = MAX_SENTENCE_LEN