tensorflow系列教程（1）之---fetch和feed的用法

#fetch

import tensorflow as tf

x=tf.Variable([1,2])
a=tf.constant([3,3])


sub=tf.subtract(x,a)
#全局变量初始化
init=tf.global_variables_initializer()


add=tf.add(x,sub)
with tf.Session() as sess:
    sess.run(init)
    print(sess.run(sub))

    print(sess.run(add))

#feed,
#创建占位符
input1=tf.placeholder(tf.float32)
input2=tf.placeholder(tf.float32)
output=tf.multiply(input1,input2)
#feed数据以字典的形式传入
with tf.Session() as sess:
    print(sess.run(output,feed_dict={input1:[7.0],input2:[2.0]}))