tensorflow学习（2）关于fetch和feed

fetch：可以取多个操作节点的值

import tensorflow as tf

input1 =tf.constant(7.0)
input2 =tf.constant(2.0)

add =tf.add(input1,input2)
mul =tf.multiply(add,input1)

with tf.Session() as sess:
    result =sess.run([add,mul])
    print (result)

feed：对占位符进行赋值，字典形式传入

import tensorflow as tf

input1 =tf.placeholder(tf.float32)
input2 =tf.placeholder(tf.float32)

mul =tf.multiply(input1,input2)

with tf.Session() as sess:
    print (sess.run(mul,feed_dict={input1:[7.],input2:[2.]}))