运行代码:
import tensorflow as tf from tensorflow.examples.tutorials.mnist import input_data # set random seed for comparing the two result calculations tf.set_random_seed(1) # this is data mnist = input_data.read_data_sets('MNIST_data', one_hot=True) # hyperparameters lr = 0.001 training_iters = 100000 batch_size = 128 n_inputs = 28 # MNIST data input (img shape: 28*28) n_steps = 28 # time steps n_hidden_units = 128 # neurons in hidden layer n_classes = 10 # MNIST classes (0-9 digits) # tf Graph input x = tf.placeholder(tf.float32, [None, n_steps, n_inputs]) y = tf.placeholder(tf.float32, [None, n_classes]) # Define weights weights = { # (28, 128) 'in': tf.Variable(tf.random_normal([n_inputs, n_hidden_units])), # (128, 10) 'out': tf.Variable(tf.random_normal([n_hidden_units, n_classes])) } biases = { # (128, ) 'in': tf.Variable(tf.constant(0.1, shape=[n_hidden_units, ])), # (10, ) 'out': tf.Variable(tf.constant(0.1, shape=[n_classes, ])) } def RNN(X, weights, biases): # hidden layer for input to cell # transpose the inputs shape from # X ==> (128 batch * 28 steps, 28 inputs) X = tf.reshape(X, [-1, n_inputs]) # into hidden # X_in = (128 batch * 28 steps, 128 hidden) X_in = tf.matmul(X, weights['in']) + biases['in'] # X_in ==> (128 batch, 28 steps, 128 hidden) X_in = tf.reshape(X_in, [-1, n_steps, n_hidden_units]) # cell ########################################## # basic LSTM Cell. cell = tf.contrib.rnn.BasicLSTMCell(n_hidden_units) # lstm cell is divided into two parts (c_state, h_state) init_state = cell.zero_state(batch_size, dtype=tf.float32) outputs, final_state = tf.nn.dynamic_rnn(cell, X_in, initial_state=init_state, time_major=False) # unpack to list [(batch, outputs)..] * steps outputs = tf.unstack(tf.transpose(outputs, [1,0,2])) results = tf.matmul(outputs[-1], weights['out']) + biases['out'] # shape = (128, 10) return results pred = RNN(x, weights, biases) cost = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(logits=pred, labels=y)) train_op = tf.train.AdamOptimizer(lr).minimize(cost) correct_pred = tf.equal(tf.argmax(pred, 1), tf.argmax(y, 1)) accuracy = tf.reduce_mean(tf.cast(correct_pred, tf.float32)) with tf.Session() as sess: init = tf.global_variables_initializer() sess.run(init) step = 0 while step * batch_size < training_iters: batch_xs, batch_ys = mnist.train.next_batch(batch_size) batch_xs = batch_xs.reshape([batch_size, n_steps, n_inputs]) sess.run([train_op], feed_dict={ x: batch_xs, y: batch_ys, }) if step % 20 == 0: print(sess.run(accuracy, feed_dict={ x: batch_xs, y: batch_ys, })) step += 1
运行结果:
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