# coding: utf-8
# In[2]:
import tensorflow as tf
from tensorflow.examples.tutorials.mnist import input_data
# In[3]:
# 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
#参数概要
def variable_summaries(var):
with tf.name_scope('summaries'):
mean=tf.reduce_mean(var)
tf.summary.scalar('mean',mean)
with tf.name_scope('stddev'):
stddev=tf.sqrt(tf.reduce_mean(tf.square(var-mean)))
tf.summary.scalar('stddev',stddev)#标准差
tf.summary.scalar('max', tf.reduce_max(var))
tf.summary.scalar('min',tf.reduce_min(var))#最小值
tf.summary.histogram('histogram',var)#直方图
#定义一个命名空间
with tf.name_scope('input'):
x = tf.placeholder(tf.float32, [None, 784],name='x_input')
y = tf.placeholder(tf.float32, [None, 10],name='y_input')
with tf.name_scope("layer"):
with tf.name_scope('weights'):
W = tf.Variable(tf.zeros([784, 10]))
variable_summaries(W)
with tf.name_scope('biases'):
b = tf.Variable(tf.zeros([10]))
variable_summaries(b)
with tf.name_scope('wx_plus_b'):
wx_plus_b=tf.matmul(x, W) + b
# 创建一个简单的神经网络
with tf.name_scope('prediction'):
prediction = tf.nn.softmax(wx_plus_b)
with tf.name_scope('loss'):
# 二次代价函数
loss = tf.reduce_mean(tf.square(y - prediction))
tf.summary.scalar('loss',loss)#
with tf.name_scope("train"):
# 使用梯度下降法
train_step = tf.train.GradientDescentOptimizer(0.2).minimize(loss)
# 初始化变量
init = tf.global_variables_initializer()
with tf.name_scope('accuracy'):
with tf.name_scope("correct_prediction"):
# 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
with tf.name_scope("accuracy"):
accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))
tf.summary.scalar('accuracy',accuracy)
#合并所有的summary
merged=tf.summary.merge_all()
with tf.Session() as sess:
sess.run(init)
writer=tf.summary.FileWriter('logs/',sess.graph)
for epoch in range(51):
for batch in range(n_batch):
batch_xs, batch_ys = mnist.train.next_batch(batch_size)
summary,_=sess.run([merged,train_step], feed_dict={x: batch_xs, y: batch_ys})
writer.add_summary(summary,epoch)
acc = sess.run(accuracy, feed_dict={x: mnist.test.images, y: mnist.test.labels})
print("Iter " + str(epoch) + ",Testing Accuracy " + str(acc))
# In[ ]:
注:tensorboard打开方式:
1:进入cmd,将dos命令移动到tensorboard文件所在的盘 这里选择 e:
2:tensorboard --logdir=E:\Py3.6_Proje\Tensorflow\logs
3:复制生成的网址,(注:不要关闭dos窗口)在Google中打开本地连接,