tensorflow中tf.reduce_mean函数的使用

reduce_mean(input_tensor,
        axis=None,
        keep_dims=False,
        name=None,
        reduction_indices=None)

import tensorflow as tf
 
x = [[1,2,3],
   [1,2,3]]
 
xx = tf.cast(x,tf.float32)
 
mean_all = tf.reduce_mean(xx, keep_dims=False)
mean_0 = tf.reduce_mean(xx, axis=0, keep_dims=False)
mean_1 = tf.reduce_mean(xx, axis=1, keep_dims=False)
 
 
with tf.Session() as sess:
  m_a,m_0,m_1 = sess.run([mean_all, mean_0, mean_1])
 
print m_a  # output: 2.0
print m_0  # output: [ 1. 2. 3.]
print m_1  #output: [ 2. 2.]

print m_a  # output: [[ 2.]]
print m_0  # output: [[ 1. 2. 3.]]
print m_1  #output: [[ 2.], [ 2.]]