# -*- coding:utf-8 -*-
import tensorflow as tf
import numpy as np
import math
import collections
import pickle as pkl
import jieba
import os
class word2vec():
def __init__(self,
vocab_list=None,
embedding_size=200,
win_len=3, # 单边窗口长
num_sampled=1000,
learning_rate=1.0,
logdir='/tmp/simple_word2vec',
model_path=None
):
# 获得模型的基本参数
self.batch_size = None # 一批中数据个数, 目前是根据情况来的
if model_path != None:
self.load_model(model_path)
else:
# model parameters
assert type(vocab_list) == list
self.vocab_list = vocab_list
self.vocab_size = vocab_list.__len__()
self.embedding_size = embedding_size
self.win_len = win_len
self.num_sampled = num_sampled
self.learning_rate = learning_rate
self.logdir = logdir
self.word2id = {} # word => id 的映射
for i in range(self.vocab_size):
self.word2id[self.vocab_list[i]] = i
# train times
self.train_words_num = 0 # 训练的单词对数
self.train_sents_num = 0 # 训练的句子数
self.train_times_num = 0 # 训练的次数(一次可以有多个句子)
# train loss records
self.train_loss_records = collections.deque(maxlen=10) # 保存最近10次的误差
self.train_loss_k10 = 0
self.build_graph()
self.init_op()
if model_path != None:
tf_model_path = os.path.join(model_path, 'tf_vars')
self.saver.restore(self.sess, tf_model_path)
def init_op(self):
self.sess = tf.Session(graph=self.graph)
self.sess.run(self.init)
def build_graph(self):
self.graph = tf.Graph()
with self.graph.as_default():
self.train_inputs = tf.placeholder(tf.int32, shape=[self.batch_size])
self.train_labels = tf.placeholder(tf.int32, shape=[self.batch_size, 1])
self.embedding_dict = tf.Variable(
tf.random_uniform([self.vocab_size, self.embedding_size], -1.0, 1.0)
)
self.nce_weight = tf.Variable(tf.truncated_normal([self.vocab_size, self.embedding_size],
stddev=1.0 / math.sqrt(self.embedding_size)))
self.nce_biases = tf.Variable(tf.zeros([self.vocab_size]))
# 将输入序列向量化
embed = tf.nn.embedding_lookup(self.embedding_dict, self.train_inputs) # batch_size
# 得到NCE损失
self.loss = tf.reduce_mean(
tf.nn.nce_loss(
weights=self.nce_weight,
biases=self.nce_biases,
labels=self.train_labels,
inputs=embed,
num_sampled=self.num_sampled,
num_classes=self.vocab_size
)
)
# 根据 nce loss 来更新梯度和embedding
self.train_op = tf.train.GradientDescentOptimizer(learning_rate=0.1).minimize(self.loss) # 训练操作
# 计算与指定若干单词的相似度
self.test_word_id = tf.placeholder(tf.int32, shape=[None])
vec_l2_model = tf.sqrt( # 求各词向量的L2模
tf.reduce_sum(tf.square(self.embedding_dict), 1, keep_dims=True)
)
self.normed_embedding = self.embedding_dict / vec_l2_model
# self.embedding_dict = norm_vec # 对embedding向量正则化
test_embed = tf.nn.embedding_lookup(self.normed_embedding, self.test_word_id)
self.similarity = tf.matmul(test_embed, self.normed_embedding, transpose_b=True)
# 变量初始化
self.init = tf.global_variables_initializer()
self.saver = tf.train.Saver()
def train_by_sentence(self, input_sentence=[]):
# input_sentence: [sub_sent1, sub_sent2, ...]
# 每个sub_sent是一个单词序列,例如['这次','大选','让']
sent_num = input_sentence.__len__()
batch_inputs = []
batch_labels = []
for sent in input_sentence:
for i in range(sent.__len__()):
start = max(0, i - self.win_len)
end = min(sent.__len__(), i + self.win_len + 1)
for index in range(start, end):
if index == i:
continue
else:
input_id = self.word2id.get(sent[i])
label_id = self.word2id.get(sent[index])
if not (input_id and label_id):
continue
batch_inputs.append(input_id)
batch_labels.append(label_id)
if len(batch_inputs) == 0:
return
batch_inputs = np.array(batch_inputs, dtype=np.int32)
batch_labels = np.array(batch_labels, dtype=np.int32)
batch_labels = np.reshape(batch_labels, [batch_labels.__len__(), 1])
feed_dict = {
self.train_inputs: batch_inputs,
self.train_labels: batch_labels
}
#_, loss_val, summary_str = self.sess.run([self.train_op, self.loss, self.merged_summary_op], feed_dict=feed_dict)
loss_val = self.sess.run([ self.loss], feed_dict = feed_dict)
# train loss
self.train_loss_records.append(loss_val)
#self.train_loss_k10 = sum(self.train_loss_records)/self.train_loss_records.__len__()
self.train_loss_k10 = np.mean(self.train_loss_records)
if self.train_sents_num % 1000 == 0:
print("{a} sentences dealed, loss: {b}"
.format(a=self.train_sents_num, b=self.train_loss_k10))
# train times
self.train_words_num += batch_inputs.__len__()
self.train_sents_num += input_sentence.__len__()
self.train_times_num += 1
def cal_similarity(self, test_word_id_list, top_k=10):
sim_matrix = self.sess.run(self.similarity, feed_dict={self.test_word_id: test_word_id_list})
sim_mean = np.mean(sim_matrix)
sim_var = np.mean(np.square(sim_matrix - sim_mean))
test_words = []
near_words = []
for i in range(test_word_id_list.__len__()):
test_words.append(self.vocab_list[test_word_id_list[i]])
nearst_id = (-sim_matrix[i, :]).argsort()[1:top_k + 1]
nearst_word = [self.vocab_list[x] for x in nearst_id]
near_words.append(nearst_word)
return test_words, near_words, sim_mean, sim_var
def save_model(self, save_path):
if os.path.isfile(save_path):
raise RuntimeError('the save path should be a dir')
if not os.path.exists(save_path):
os.mkdir(save_path)
# 记录模型各参数
model = {}
var_names = ['vocab_size', # int model parameters
'vocab_list', # list
'learning_rate', # int
'word2id', # dict
'embedding_size', # int
'logdir', # str
'win_len', # int
'num_sampled', # int
'train_words_num', # int train info
'train_sents_num', # int
'train_times_num', # int
'train_loss_records', # int train loss
'train_loss_k10', # int
]
for var in var_names:
model[var] = eval('self.' + var)
param_path = os.path.join(save_path, 'params.pkl')
if os.path.exists(param_path):
os.remove(param_path)
with open(param_path, 'wb') as f:
pkl.dump(model, f)
# 记录tf模型
tf_path = os.path.join(save_path, 'tf_vars')
if os.path.exists(tf_path):
os.remove(tf_path)
self.saver.save(self.sess, tf_path)
def load_model(self, model_path):
if not os.path.exists(model_path):
raise RuntimeError('file not exists')
param_path = os.path.join(model_path, 'params.pkl')
with open(param_path, 'rb') as f:
model = pkl.load(f)
self.vocab_list = model['vocab_list']
self.vocab_size = model['vocab_size']
self.logdir = model['logdir']
self.word2id = model['word2id']
self.embedding_size = model['embedding_size']
self.learning_rate = model['learning_rate']
self.win_len = model['win_len']
self.num_sampled = model['num_sampled']
self.train_words_num = model['train_words_num']
self.train_sents_num = model['train_sents_num']
self.train_times_num = model['train_times_num']
self.train_loss_records = model['train_loss_records']
self.train_loss_k10 = model['train_loss_k10']
if __name__ == '__main__':
# step 1 读取停用词
stop_words = []
with open('stop_words.txt', encoding='utf-8') as f:
line = f.readline()
while line:
stop_words.append(line[:-1])
line = f.readline()
stop_words = set(stop_words)
print('停用词读取完毕,共{n}个单词'.format(n=len(stop_words)))
# step2 读取文本,预处理,分词,得到词典
raw_word_list = []
sentence_list = []
with open('2800.txt', encoding='gbk') as f:
line = f.readline()
while line:
while '\n' in line:
line = line.replace('\n', '')
while ' ' in line:
line = line.replace(' ', '')
if len(line) > 0: # 如果句子非空
raw_words = list(jieba.cut(line, cut_all=False))
dealed_words = []
for word in raw_words:
if word not in stop_words and word not in ['qingkan520', 'www', 'com', 'http']:
raw_word_list.append(word)
dealed_words.append(word)
sentence_list.append(dealed_words)
line = f.readline()
word_count = collections.Counter(raw_word_list)
print('文本中总共有{n1}个单词,不重复单词数{n2},选取前30000个单词进入词典'
.format(n1=len(raw_word_list), n2=len(word_count)))
word_count = word_count.most_common(30000)
word_list = [x[0] for x in word_count]
# 创建模型,训练
w2v = word2vec(vocab_list=word_list, # 词典集
embedding_size=200,
win_len=2,
learning_rate=1,
num_sampled=100, # 负采样个数
#logdir='/tmp/280'
) # tensorboard记录地址
num_steps = 10000
for i in range(num_steps):
# print (i%len(sentence_list))
sent = sentence_list[i % len(sentence_list)]
w2v.train_by_sentence([sent])
w2v.save_model('model')
w2v.load_model('model')
test_word = ['天地', '级别']
test_id = [word_list.index(x) for x in test_word]
# print('test_id', test_id)
test_words, near_words, sim_mean, sim_var = w2v.cal_similarity(test_id)
print(test_words, near_words, sim_mean, sim_var)
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