Tensorflow - Variables

Code:

import tensorflow as tf

x = tf.Variable([1, 2])
a = tf.constant([3, 3])
#Add a subtraction op
sub = tf.subtract(x, a)
#Add an addition op
add = tf.add(x, sub)

#variables to be initialized
init = tf.global_variables_initializer()

with tf.Session() as sess:
    # Initialize variables first
    sess.run(init)
    print (sess.run (sub))
    print (sess.run (add))

operation result:

[-2 -1]
[-1  1]

Code:

#Variables can be named
#Create a variable initialized to 0
state = tf.Variable(0, name='counter')

#Create an op, the role is to increase the state by 1
new_value = tf.add(state, 1)
#Create assignment op, assign new_value to state
updata = tf.assign(state, new_value)

#variable initialization
init = tf.global_variables_initializer()

with tf.Session() as sess:
    sess.run(init)
    print (sess.run (state))
    #loop 5 times
    for _ in range(5):
        sess.run(updata)
        print (sess.run (state))

operation result:

0
1
2
3
4
5