Mnist数据集用神经网络处理-tensorflow实现

import tensorflow as tf from tensorflow.examples.tutorials.mnist import input_datamnist = input_data.read_data_sets('./mnist/', one_hot=True)INPUT_SIZE = 28 HIDDEN1_SIZE = 256 HIDDEN2_SIZE = 256 LR = 0.002 N_CLASSES = 10 TRAINING_EPOCH = 25 BATCH_SIZE = 50X = tf.placeholder(tf.float32, [None, INPUT_SIZE * INPUT_SIZE]) Y = tf.placeholder(tf.float32, [None, N_CLASSES])W1 = tf.Variable(tf.random_normal([INPUT_SIZE * INPUT_SIZE, HIDDEN1_SIZE])) b1 = tf.Variable(tf.random_normal([HIDDEN1_SIZE])) L1=tf.nn.sigmoid(tf.matmul(X,W1) + b1)W2 = tf.Variable(tf.random_normal([HIDDEN1_SIZE, HIDDEN2_SIZE])) b2 = tf.Variable(tf.random_normal([HIDDEN2_SIZE])) L2=tf.nn.sigmoid(tf.matmul(L1,W2) + b2)W3 = tf.Variable(tf.random_normal([HIDDEN1_SIZE, HIDDEN2_SIZE])) b3 = tf.Variable(tf.random_normal([HIDDEN2_SIZE])) L3=tf.nn.sigmoid(tf.matmul(L2,W3) + b3)W = tf.Variable(tf.random_normal([HIDDEN2_SIZE, N_CLASSES])) b = tf.Variable(tf.random_normal([N_CLASSES])) hypothesis = tf.nn.sigmoid(tf.matmul(L3,W) + b) #损失函数 cost = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(logits = hypothesis,labels = Y)) #ada梯度下降 optimizer=tf.train.AdamOptimizer(learning_rate=LR).minimize(cost)sess = tf.Session() sess.run(tf.global_variables_initializer())#全部初始化print('Learning stared. It takes sometime.') for epoch in range(TRAINING_EPOCH):#25次 avg_cost = 0 total_batch = int(mnist.train.num_examples / BATCH_SIZE) for i in range(total_batch): batch_xs, batch_ys = mnist.train.next_batch(BATCH_SIZE) c, _, = sess.run([cost, optimizer], feed_dict= {X: batch_xs, Y: batch_ys}) avg_cost += c / total_batch print('Epoch:', '%04d' % (epoch + 1), 'cost =', '{:.9f}'.format(avg_cost)) print('Learning Finished!')correct_prediction = tf.equal(tf.argmax(hypothesis, 1), tf.argmax(Y, 1))#查看预测和正确相等的 accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))#bool型转为float print('Accuracy:', sess.run(accuracy, feed_dict={X: mnist.test.images, Y: mnist.test.labels}))#显示准确率

【Mnist数据集用神经网络处理-tensorflow实现】Mnist数据集用神经网络处理-tensorflow实现
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