import tensorflow as tf

condition = tf.placeholder(tf.int32, name="condition")

A = tf.constant(value=123)
B = tf.constant(value=321)

def func1():
return A

def func2():
return B

y = tf.cond(condition > 0, func1, func2) # tensor 和 非tensor 比较

sess = tf.Session()

feed_dict = {condition:1}
print(sess.run(y,feed_dict=feed_dict))

feed_dict = {condition:-1}
print(sess.run(y,feed_dict=feed_dict))

打印结果:
123
321