tensorflow实战笔记（18）----textCNN
一、import 包
import os import pandas as pd import csv import time import datetime import numpy as np import tensorflow as tf import re import sys from __future__ import print_function import matplotlib.pyplot as plt from tqdm import tqdm
二、数据处理：
1、问题：将【句子，click label】数据进行点击二分类预测。
数据：show数据（展示广告log）：句子，click数据（点击广告log)：句子。还有word2vec一个词向量词典：(词，vec)。
2、由于数据量有点大，总体数据有一亿个样本，其中需要做的数据处理有：
1、show和click数据都去重去空并将show数据进行分词----show:【句子，分词】【在集群上采用pig脚本跑】
2、由于有（show 数据)和(click 数据)，两者需要做left Join获取标签，即如果show在click中出现，则其label为1，否则为0。最终数据样本形式为 show:【句子，click label】。
然后对句子的分词进行word count 转化为Word id。
然后将word ID 和Word2vec进行mapping，即【word，ID，vec】，需要放入模型中。
然后将word ID 和 show:【句子，click label】，show:【句子，分词】进行leftJoin以及map，转成【句子，词1ID，词2ID，词3ID……，label】（每个句子固定有36个词，不够则补ID 0，超过则砍掉），需要放入模型中。
Scala代码：
import com.qihoo.spark.app.SparkAppJob import org.apache.spark.SparkContext import org.apache.spark.sql.expressions.Window import org.apache.spark.sql.{DataFrame, Dataset, SparkSession} import org.kohsuke.args4j.{Option => ArgOption} import org.apache.spark.sql.functions._ class DataProcessJob extends SparkAppJob { //input @ArgOption(name = "-word-vector-input", required = true, aliases = Array("--wordVecInput"), usage = "wordVecInput") var wordVecInput: String = _ @ArgOption(name = "-sentence-segment-input", required = true, aliases = Array("--sentenceSegInput"), usage = "sentenceSegInput") var sentenceSegInput: String = _ @ArgOption(name = "-sentence-label-input", required = true, aliases = Array("--sentenceLabelInput"), usage = "sentenceLabelInput") var sentenceLabelInput: String = _ //output @ArgOption(name = "-word-id-vector-output", required = true, aliases = Array("--wordIdVecOutput"), usage = "wordIdVecOutput") var wordIdVecOutput: String = _ @ArgOption(name = "-sentence-ids-label-output", required = true, aliases = Array("--sentenceIdsLabelOutput"), usage = "sentenceIdsLabelOutput") var sentenceIdsLabelOutput: String = _ override protected def run(sc: SparkContext): Unit = { import sparkSession.implicits._ val sentenceSegmentRaw = sparkSession.read.text(sentenceSegInput).as[String].filter(_.trim.length() != 0) sentenceSegmentRaw.show() val wordVectorRaw = sparkSession.read.text(wordVecInput).as[String].filter(_.trim.length() != 0) wordVectorRaw.show() val sentenceLabelRaw = sparkSession.read.text(sentenceLabelInput).as[String].filter(_.trim.length() != 0) sentenceLabelRaw.show() val n = 36 val (wordIdVec,sentenceIdsLabel) = wordCountMapVectorJob.getWordId(sparkSession,sentenceSegmentRaw,wordVectorRaw,sentenceLabelRaw,n) wordIdVec.show() sentenceIdsLabel.show() val concatWordIdVec = wordIdVec.select(concat_ws("\t", $"word", $"id",$"vec")) concatWordIdVec.write.text(wordIdVecOutput) val concatSentenceIdsLabel = sentenceIdsLabel.select(concat_ws("\t", $"_1", $"_2",$"_3")) concatSentenceIdsLabel.write.text(sentenceIdsLabelOutput) } } object wordCountMapVectorJob { def getWordId(sparkSession: SparkSession, sentenceSegmentRaw: Dataset[String], wordVectorRaw: Dataset[String], sentenceLabelRaw: Dataset[String], n: Int):(DataFrame,Dataset[(String,String, Int)]) = { import sparkSession.implicits._ //get wordSegment rows def sentenceSegmentRows(line: String) = { val tokens = line.split("\t", 2) (tokens(0), tokens(1)) } //get wordVec rows def wordVecRows(line: String) = { val tokens = line.split(" ", 2) (tokens(0), tokens(1)) } //get WordsLabel rows def sentenceLabelRows(line: String) = { val tokens = line.split("\t") (tokens(0), tokens(1).toInt) } //wordCount def wordCountJob(segment: Dataset[String]) = { val wordCount = segment .map(line => line.split("\t")) .flatMap(line => line(1).trim.split(" ")) .groupByKey(value => value) .count() .withColumnRenamed("count(1)", "count") wordCount } // create three DataFrame val sentenceSegmentDf = sentenceSegmentRaw.map(sentenceSegmentRows).toDF("sentence", "segment") val wordVec = wordVectorRaw.map(wordVecRows).toDF("word", "vec") val sentenceLabelDf = sentenceLabelRaw.map(sentenceLabelRows).toDF("sentence", "label") //get word Id val wordCount = wordCountJob(sentenceSegmentRaw) val wordCountJoinVec = wordCount.join(wordVec, wordCount("value") === wordVec("word"), "inner") val idDf = Window.partitionBy().orderBy($"value") val wordVecAddIdDf = wordCountJoinVec.withColumn("id", row_number().over(idDf)) val wordIdVec = wordVecAddIdDf.select("word", "id","vec") wordIdVec.show() //get each sentence segment ID and label val wordDictMap = wordIdVec.map(row => (row.getString(0), row.getInt(1))).rdd.collectAsMap() val wordDictMapBd = sparkSession.sparkContext.broadcast(wordDictMap) // sentenceSegmentDf left join sentenceLabelDf => ( segment , label ) val segmentLeftJoinLabel = sentenceSegmentDf.join(sentenceLabelDf, sentenceSegmentDf("sentence") === sentenceLabelDf("sentence"), "inner") segmentLeftJoinLabel.printSchema() segmentLeftJoinLabel.show() // segmentLabel => ( IDs , label ) val IDLabel = segmentLeftJoinLabel.map { r => val ids = r.getString(1).trim().split(" ").map(wordDictMapBd.value.getOrElse(_, 0)) val fixLengthIds = if (ids.length < n) ids.padTo(n, 0) else ids.slice(0, n) val stringIds = fixLengthIds.mkString(" ") (r.getString(0),stringIds, r.getInt(3)) } (wordIdVec , IDLabel) } }
总结：最终放入模型中的数据有：【词1ID，词2ID，词3ID……，label】，【ID，vec】，因为embedding_lookup (【ID，vec】,【词1ID，词2ID，词3ID……，label】)需要这种格式。
3、读入Python中进行的数据处理：
第一次执行Python脚本时：
# load data train_data = pd.read_csv('./data/train_data/traindata.txt',sep = '\t',quoting = csv.QUOTE_NONE, header = None,names = ['sentence','ids','label']) ## lower_sample 下采样 des = train_data['label'].value_counts() print("positive number : {:d} and negtive number : {:d} ,pos/neg : {:d} / 1".format(des[1] , des[0] , des[0]/des[1])) def lower_sample(train_data,percent): pos_data = train_data[train_data['label'] == 1] neg_data = train_data[train_data['label'] == 0] neg , pos = len(neg_data), len(pos_data) index = np.random.choice( neg ,size = percent * pos ,replace = False) lower_sample = neg_data.iloc[list(index)] return(pd.concat([pos_data, lower_sample])) percent = 2 lower_data = lower_sample(train_data,percent)
再优化一下，因为从文本中读取：【句子，词1ID，词2ID，词3ID……，label】还需要进行string.split()处理，还是比较耗时，所以以下代码采用np.save来存储【词1ID，词2ID，词3ID……，label】，这样再采用np.load加载比较快速，而且不包含句子文本数据。
（第一次也要运行）如果是第二次执行该脚本，就直接运行以下代码加载x和y，不用运行上面的代码读取traindata了。
# get data x and y TRAIN_X_NPY='./data/train_data/train_sequence_data_x.npy' TRAIN_Y_NPY='./data/train_data/train_sequence_data_y.npy' SENTENCE_ONLY='./data/train_data/train_sentence_data.txt' if os.path.exists(TRAIN_X_NPY) and os.path.exists(TRAIN_Y_NPY): x = np.load(TRAIN_X_NPY) y = np.load(TRAIN_Y_NPY) else: chunksize = train_data.count()[1] ndim = 36 y = np.array(train_data['label']) x = np.zeros((chunksize, ndim)) for i,line in tqdm(enumerate(train_data['ids'])): x[i] = np.array(list(map(int,line.strip().split(" ")))) np.save(TRAIN_X_NPY, x) np.save(TRAIN_Y_NPY, y) text_data = list(train_data['sentence']) with open(SENTENCE_ONLY, 'w') as f: for line in text_data: f.write(line) f.write('\n') ## data x and y lower sample pos_indices = [index for index,label in enumerate(list(y)) if label > 0] neg_indices = [index for index, label in enumerate(list(y)) if label <= 0] sampled_neg_indices = np.random.choice(neg_indices, len(neg_indices) / 5, replace=False) x = np.concatenate((x[sampled_neg_indices],x[pos_indices]), axis=0) y = np.concatenate((y[sampled_neg_indices],y[pos_indices])) print('sampled shape: x %d, %d, y %d' % (x.shape[0], x.shape[1], y.shape[0]))
加载【ID，vec】词向量
# embedding_map EMBEDDING_SIZE = 100 embedding_map = pd.read_csv('./data/train_data/idvec.txt',sep = '\t',quoting = csv.QUOTE_NONE, header = None,names = ['word','id','vec']) embedded_rows = embedding_map.count()[1] embedding_map = embedding_map.sort_values(by = 'id') embedded_mat = np.zeros((embedded_rows + 1, EMBEDDING_SIZE)) def get_embedded_mat(embedding_map , embedded_rows , EMBEDDING_SIZE): for i,line in enumerate(embedding_map['vec']): if i != 0: embedded_mat[i] = np.array(list(map(float,line.strip().split(' ')))) return embedded_mat embedded_mat = get_embedded_mat(embedding_map , embedded_rows , EMBEDDING_SIZE)
shuffle数据集和切分训练集和测试集，注意测试集不要分太大，本来分了79万数据，（dev_sample_ratio = 0.05），training时报错：resource ehxousted error，训练test step时会OOM。
# Data Preparation # ================================================== # Randomly shuffle data np.random.seed(100) dev_sample_ratio = 0.01 n = len(y) ## undersample indices = [i for i in range(n)] shuffle_indices = np.random.permutation(indices) x_shuffled = [x[i] for i in shuffle_indices] y_shuffled = [y[i] for i in shuffle_indices] # Split train/test set # TODO: This is very crude, should use cross-validation dev_sample_index = np.int(dev_sample_ratio * len(shuffle_indices)) x_dev, x_train = x_shuffled[:dev_sample_index], x_shuffled[dev_sample_index:] y_dev, y_train = y_shuffled[:dev_sample_index], y_shuffled[dev_sample_index:] # del x, y, x_shuffled, y_shuffled ## train_pos : train_neg = 2037815 : 11109457 = 5 ## Test_pos : Test_neg: 226257 : 1234551 = 5 print("Train/Dev split: {:d}/{:d}".format(len(y_train), len(y_dev))) print("Train_pos and Train_neg: {:f} {:f}".format(int(sum(y_train)) , int(len(y_train)-sum(y_train)))) print("Test_pos and Test_neg: {:f} {:f}".format(int(sum(y_dev)) , int(len(y_dev)-sum(y_dev)))) print("Test_neg / Test_all: {:f}".format((len(y_dev)-sum(y_dev))/float(len(y_dev))))
三、模型搭建
class TextCNN(object): """ A CNN for text classification. Uses an embedding layer, followed by a convolutional, max-pooling and softmax layer. """ def __init__( self, sequence_length, num_classes, embedding_size, filter_sizes, num_filters, embedding_matrix, early_stop_steps=3000, learning_rate = 0.01, nRestarts = 10, restart = 0, l2_reg_lambda=0.0): # Placeholders for input, output and dropout self.input_x = tf.placeholder(tf.int64, [None, sequence_length], name="input_x") self.input_y = tf.placeholder(tf.int64, [None, num_classes], name="input_y") self.dropout_keep_prob = tf.placeholder(tf.float32, name="dropout_keep_prob") self.best_dev_tstep = 0 self.best_dev_loss = 999 self.learning_rate = learning_rate self.best_model_path = '' self.early_stop_steps = early_stop_steps self.restart = restart self.nRestarts = nRestarts # Keeping track of l2 regularization loss (optional) l2_loss = tf.constant(0.0) # Embedding layer for fine-tune with tf.device('/gpu:0'), tf.name_scope("embedding"): self.W = tf.Variable( tf.constant(embedding_matrix, dtype=tf.float32, name='pre_weights'), name="W", trainable=True) self.embedded_chars = tf.nn.embedding_lookup(self.W, self.input_x) self.embedded_chars_expanded = tf.expand_dims(self.embedded_chars, -1) # Create a convolution + maxpool layer for each filter size pooled_outputs = [] for i, filter_size in enumerate(filter_sizes): with tf.name_scope("conv-maxpool-%s" % filter_size): # Convolution Layer filter_shape = [filter_size, embedding_size, 1, num_filters] W = tf.Variable(tf.truncated_normal(filter_shape, stddev=0.1), name="W") b = tf.Variable(tf.constant(0.1, shape=[num_filters]), name="b") conv = tf.nn.conv2d( self.embedded_chars_expanded, W, strides=[1, 1, 1, 1], padding="VALID", name="conv") # Apply nonlinearity h = tf.nn.relu(tf.nn.bias_add(conv, b), name="relu") # Maxpooling over the outputs pooled = tf.nn.max_pool( h, ksize=[1, sequence_length - filter_size + 1, 1, 1], strides=[1, 1, 1, 1], padding='VALID', name="pool") pooled_outputs.append(pooled) # Combine all the pooled features num_filters_total = num_filters * len(filter_sizes) self.h_pool = tf.concat(pooled_outputs, 3) self.h_pool_flat = tf.reshape(self.h_pool, [-1, num_filters_total]) # Add dropout with tf.name_scope("dropout"): self.h_drop = tf.nn.dropout(self.h_pool_flat, self.dropout_keep_prob) # Final (unnormalized) scores and predictions with tf.name_scope("output"): W = tf.get_variable( "W", shape=[num_filters_total, num_classes], initializer=tf.contrib.layers.xavier_initializer()) b = tf.Variable(tf.constant(0.1, shape=[num_classes]), name="b") l2_loss += tf.nn.l2_loss(W) l2_loss += tf.nn.l2_loss(b) self.scores = tf.sigmoid(tf.nn.xw_plus_b(self.h_drop, W, b, name="scores"), name="sigmoid_scores") self.predictions = tf.cast(self.scores > 0.5, tf.int64,name = "predictions") # Calculate mean cross-entropy loss with tf.name_scope("loss"): losses = tf.nn.sigmoid_cross_entropy_with_logits(logits=self.scores, labels=tf.cast(self.input_y, tf.float32)) self.loss = tf.reduce_mean(losses) + l2_reg_lambda * l2_loss # Accuracy with tf.name_scope("accuracy"): corrected_prediction = tf.equal(self.predictions, self.input_y) self.accuracy = tf.reduce_mean(tf.cast(corrected_prediction, tf.float32), name="accuracy")
三、训练模型
tf.nn.conv2d( input,filter,strides,padding,use_cudnn_on_gpu=True,data_format='NHWC',dilations=[1, 1, 1, 1],name=None)
input tensor shape：[batch, in_height, in_width, in_channels]
filter tensor shape：[filter_height, filter_width, in_channels, out_channels]
##取batch_size数据 def batch_iter_for_list(x_train, y_train, batch_size = 512, num_epochs = 50, shuffle = True): num_data = len(y_train) num_batches_per_epoch = int((len(y_train)-1) / batch_size) + 1 for epoch in range(num_epochs): print("===============epoch{}===============".format(epoch + 1)) for batch_num in range(num_batches_per_epoch): start_index = batch_num * batch_size end_index = min((batch_num + 1) * batch_size, num_data) yield x_train[start_index:end_index], np.array(y_train[start_index: end_index]).reshape(-1, 1) # Training # ================================================== if __name__ == '__main__': filter_size = [1,2,3, 5] nfilter = 100 ndim = 36 num_classes = 1 # vocab_length = embedding_map.count()[0] EMBEDDING_SIZE = 100 early_stop_steps = -1 l2_reg_lambda=0.0 nRestarts = 8 # reduce on plateau, the best checkpoint will be restored and the #learning rate will be halved # reset_graph() embedding_matrix_rand = np.random.normal(size = embedded_mat.shape) with tf.Graph().as_default(): os.environ["CUDA_VISIBLE_DEVICES"] = "0" config = tf.ConfigProto() # config.gpu_options.per_process_gpu_memory_fraction = 0.5 config.gpu_options.allow_growth=True # allocate when needed sess = tf.Session(config = config) with sess.as_default(): global_step = tf.Variable(0, name="global_step", trainable=False) learning_rate = tf.train.exponential_decay(0.1,global_step,1000,0.96,staircase = True) cnn = TextCNN( sequence_length = ndim, # vocab_length = vocab_length, num_classes = num_classes, embedding_size = EMBEDDING_SIZE, filter_sizes = filter_size, num_filters = nfilter, embedding_matrix = embedded_mat, early_stop_steps = early_stop_steps, learning_rate = learning_rate, nRestarts = nRestarts, l2_reg_lambda = l2_reg_lambda) # Define Training procedure # 定义GD优化器 # optimizer = tf.train.GradientDescentOptimizer(cnn.learning_rate) optimizer = tf.train.AdamOptimizer() grads_and_vars = optimizer.compute_gradients(cnn.loss) train_op = optimizer.apply_gradients(grads_and_vars, global_step=global_step) # Output directory for models and summaries timestamp = str(int(time.time())) out_dir = os.path.abspath(os.path.join(os.path.curdir, "runs", timestamp)) print("Writing to {}\n".format(out_dir)) # Summaries for loss and accuracy loss_summary = tf.summary.scalar("loss", cnn.loss) acc_summary = tf.summary.scalar("accuracy", cnn.accuracy) # Train Summaries # train_summary_op = tf.summary.merge([loss_summary, acc_summary, grad_summaries_merged]) train_summary_op = tf.summary.merge([loss_summary, acc_summary]) train_summary_dir = os.path.join(out_dir, "summaries", "train") train_summary_writer = tf.summary.FileWriter(train_summary_dir, sess.graph) # Dev summaries dev_summary_op = tf.summary.merge([loss_summary, acc_summary]) dev_summary_dir = os.path.join(out_dir, "summaries", "dev") dev_summary_writer = tf.summary.FileWriter(dev_summary_dir, sess.graph) # Checkpoint directory. Tensorflow assumes this directory already exists so we need to create it checkpoint_dir = os.path.abspath(os.path.join(out_dir, "checkpoints")) checkpoint_prefix = os.path.join(checkpoint_dir, "model") if not os.path.exists(checkpoint_dir): os.makedirs(checkpoint_dir) saver = tf.train.Saver(tf.global_variables(), max_to_keep=1) # Write vocabulary # vocab_processor.save(os.path.join(out_dir, "vocab")) # Initialize all variables sess.run(tf.global_variables_initializer()) def train_step(x_batch, y_batch, writer=None): """ A single training step """ feed_dict = { cnn.input_x: x_batch, cnn.input_y: y_batch, cnn.dropout_keep_prob: 0.8 } _, step, loss, accuracy , predictions , scores, train_summary = sess.run( [train_op, global_step, cnn.loss, cnn.accuracy , cnn.predictions , cnn.scores, train_summary_op], feed_dict) time_str = datetime.datetime.now().isoformat() if step % 10 == 0: print("train: {}: step {}, loss {:g}, acc {:g}".format(time_str, step, loss, accuracy)) if writer: writer.add_summary(train_summary, step) def dev_step(x_batch, y_batch, writer=None): """ Evaluates model on a dev set """ feed_dict = { cnn.input_x: x_batch, cnn.input_y: y_batch, cnn.dropout_keep_prob: 1.0 } step, summaries, loss, accuracy = sess.run( [global_step, dev_summary_op, cnn.loss, cnn.accuracy], feed_dict) if loss < cnn.best_dev_loss: cnn.best_dev_loss = loss cnn.best_dev_tstep = step if step > 100: # min steps to checkpoint path = saver.save(sess, checkpoint_prefix, global_step=step) cnn.best_model_path = path if step % 100 == 0: print("val-loss {} Saved model checkpoint to {}\n".format(loss, path)) time_str = datetime.datetime.now().isoformat() print("val: {}: step {}, loss {:g}, acc {:g}".format(time_str, step, loss, accuracy)) if writer: writer.add_summary(summaries, step) # print cnn.nRestarts, cnn.restart, cnn.best_dev_loss, cnn.best_dev_tstep, cnn.best_model_path # early stopping if cnn.early_stop_steps > 0: if step - cnn.best_dev_tstep > cnn.early_stop_steps: if cnn.restart >= cnn.nRestarts: print('best validation loss of {} at training setp {}'.format( cnn.best_dev_loss, cnn.best_dev_tstep)) print('early stopping: end training.') return True else: if len(cnn.best_model_path) == 0: print('Not find best model: end training.') return True else: print('restore best model from ' + cnn.best_model_path + 'at step '\ + str(cnn.best_dev_tstep)) saver.restore(sess, cnn.best_model_path) cnn.learning_rate /= 2.0 cnn.early_stop_steps /= 2 step = cnn.best_dev_tstep cnn.restart += 1 return False else: return False else: return False # Generate batches batches = batch_iter_for_list(x_train, y_train, batch_size = 512 , num_epochs = 1000) y_dev_input = np.array(y_dev).reshape(-1, 1) # Training loop. For each batch... for batch_index, (x_batch, y_batch) in enumerate(batches): train_step(x_batch, y_batch, writer=train_summary_writer) if batch_index % 100 == 0: early_stop_flag = dev_step(x_dev, y_dev_input, writer=dev_summary_writer) if early_stop_flag: break
最后train loss收敛在0.63左右，acc最好在0.90，一般为0.85。
val loss收敛在0.63，acc收敛在0.85左右。
参考：
http://www.yidianzixun.com/article/0KNcfHXG
https://www.cnblogs.com/pinard/p/6744056.html
