模型的保存
import tensorflow as tf
from tensorflow.examples.tutorials.mnist import input_data
# 载入数据集
mnist = input_data.read_data_sets("MNIST_data", one_hot=True)
# 每个批次的大小
batch_size = 100
# 计算一共有多少个批次
n_batch = mnist.train.num_examples // batch_size
# 定义两个placeholder
x = tf.placeholder(tf.float32, [None, 784])
y = tf.placeholder(tf.float32, [None, 10])
# 创建一个简单的神经网络
W = tf.Variable(tf.zeros([784, 10]))
b = tf.Variable(tf.zeros([1, 10]))
prediction = tf.nn.softmax(tf.matmul(x, W) + b)
# 定义二次代价函数
loss = tf.reduce_mean(tf.square(y - prediction))
# 交叉熵
# loss = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(labels= y, logits= prediction))
# 定义梯度下降法
train_step = tf.train.GradientDescentOptimizer(0.2).minimize(loss)
# 初始化变量
init = tf.global_variables_initializer()
# 结果存储在一个布尔型列表中
correct_prediction = tf.equal(tf.argmax(y,1), tf.argmax(prediction, 1))
# 求准确率
accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))
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))
# 保存训练好的网络模型
saver = tf.train.Saver()
saver.save(sess, 'net/my_net.ckpt')
模型的加载
import tensorflow as tf
from tensorflow.examples.tutorials.mnist import input_data
# 载入数据集
mnist = input_data.read_data_sets("MNIST_data", one_hot=True)
# 每个批次的大小
batch_size = 100
# 计算一共有多少个批次
n_batch = mnist.train.num_examples // batch_size
# 定义两个placeholder
x = tf.placeholder(tf.float32, [None, 784])
y = tf.placeholder(tf.float32, [None, 10])
# 创建一个简单的神经网络
W = tf.Variable(tf.zeros([784, 10]))
b = tf.Variable(tf.zeros([1, 10]))
prediction = tf.nn.softmax(tf.matmul(x, W) + b)
# 定义二次代价函数
loss = tf.reduce_mean(tf.square(y - prediction))
# 交叉熵
# loss = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(labels= y, logits= prediction))
# 定义梯度下降法
train_step = tf.train.GradientDescentOptimizer(0.2).minimize(loss)
# 初始化变量
init = tf.global_variables_initializer()
# 结果存储在一个布尔型列表中
correct_prediction = tf.equal(tf.argmax(y,1), tf.argmax(prediction, 1))
# 求准确率
accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))
with tf.Session() as sess:
sess.run(init)
print(sess.run(accuracy, feed_dict={x: mnist.test.images, y: mnist.test.labels}))
saver = tf.train.Saver()
saver.restore(sess, 'net/my_net.ckpt')
print(sess.run(accuracy, feed_dict={x: mnist.test.images, y: mnist.test.labels}))