Getting Started With TensorFlow¶

import tensorflow as tf
tf.__version__

3 # a rank 0 tensor; this is a scalar with shape []
[1. ,2., 3.] # a rank 1 tensor; this is a vector with shape [3]
[[1., 2., 3.], [4., 5., 6.]] # a rank 2 tensor; a matrix with shape [2, 3]
[[[1., 2., 3.]], [[7., 8., 9.]]] # a rank 3 tensor with shape [2, 1, 3]

node1 = tf.constant(3.0, tf.float32)
node2 = tf.constant(4.0) # also tf.float32 implicitly
print(node1, node2)

sess = tf.Session()
print(sess.run([node1, node2]))

node3 = tf.add(node1, node2)
print("node3: ", node3)
print("sess.run(node3): ",sess.run(node3))

a = tf.placeholder(tf.float32)
b = tf.placeholder(tf.float32)
adder_node = a + b  # + provides a shortcut for tf.add(a, b)

print(sess.run(adder_node, feed_dict={a: 3, b:4.5}))
print(sess.run(adder_node, feed_dict={a: [1,3], b: [2, 4]}))

add_and_triple = adder_node * 3.
print(sess.run(add_and_triple, feed_dict={a: 3, b:4.5}))