1、RNN(Recurrent Neural Network)循环神经网络模型
详见RNN循环神经网络:https://www.cnblogs.com/pinard/p/6509630.html
2、LSTM(Long Short Term Memory)长短期记忆神经网络模型
详见LSTM长短期记忆神经网络:http://www.cnblogs.com/pinard/p/6519110.html
3、LSTM长短期记忆神经网络处理Mnist数据集
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import tensorflow as tf from tensorflow.examples.tutorials.mnist import input_data from tensorflow.contrib import rnn # 载入数据集 mnist = input_data.read_data_sets( "MNIST_data/" , one_hot = True ) # 输入图片是28*28 n_inputs = 28 # 输入一行,一行有28个数据(28个像素点),即输入序列长度为28 max_time = 28 # 一共28行 lstm_size = 100 # 隐层单元 n_classes = 10 # 10个分类 batch_size = 50 # 每批次50个样本 n_batch = mnist.train.num_examples / / batch_size # 计算一共有多少个批次 # 这里的none表示第一个维度可以是任意的长度 x = tf.placeholder(tf.float32, [ None , 784 ]) # 正确的标签 y = tf.placeholder(tf.float32, [ None , 10 ]) # 初始化权值 weights = tf.Variable(tf.truncated_normal([lstm_size, n_classes], stddev = 0.1 )) # 初始化偏置值 biases = tf.Variable(tf.constant( 0.1 , shape = [n_classes])) # 定义RNN网络 def RNN(X, weights, biases): inputs = tf.reshape(X, [ - 1 , max_time, n_inputs]) # 定义LSTM基本CELL lstm_cell = rnn.BasicLSTMCell(lstm_size) # final_state[0]是cell state # final_state[1]是hidden_state outputs, final_state = tf.nn.dynamic_rnn(lstm_cell, inputs, dtype = tf.float32) results = tf.nn.softmax(tf.matmul(final_state[ 1 ], weights) + biases) return results # 计算RNN的返回结果 prediction = RNN(x, weights, biases) # 损失函数 cross_entropy = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(logits = prediction, labels = y)) # 使用AdamOptimizer进行优化 train_step = tf.train.AdamOptimizer( 1e - 4 ).minimize(cross_entropy) # 结果存放在一个布尔型列表中 correct_prediction = tf.equal(tf.argmax(y, 1 ), tf.argmax(prediction, 1 )) # argmax返回一维张量中最大的值所在的位置 # 求准确率 accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32)) # 把correct_prediction变为float32类型 # 初始化 init = tf.global_variables_initializer() with tf.Session() as sess: sess.run(init) for epoch in range ( 21 ): for batch in range (n_batch): batch_xs, batch_ys = mnist.train.next_batch(batch_size) sess.run(train_step, feed_dict = {x: batch_xs, y: batch_ys}) acc = sess.run(accuracy, feed_dict = {x: mnist.test.images, y: mnist.test.labels}) print ( "Iter " + str (epoch) + ", Testing Accuracy= " + str (acc)) |
结果为: