構建第一軸形狀的條件圖在張量流中爲「無」

Question

當在圖構建階段時，假設張量x這是一個神經網絡的完全連接層。

因此假設x的形狀是(?, 5)。我想設置的最後一列像這樣的Python：

for i in range(x.shape[0]): 
    if x[i,-1] < 0.5: 
     x[i,-1] = 0.0 
    else: 
     x[i,-1] = 1.0 

我只能用tf.cond當x只有1行是這樣的：

# const3 and const4 are constant mask 
out = tf.cond(tf.greater(out[-1], tf.constant(0.5)), 
       lambda: tf.add(tf.multiply(out, const3), const4), 
       lambda: tf.multiply(out, const3)) 

如何檢查的x時，第一個維度以上是?？

Answer 1

是否這樣？

import tensorflow as tf 
import numpy as np 

a = tf.placeholder(tf.int32, shape=[None, 5]) 

r, c = a.get_shape() 
x_split = tf.split(1, c, a) # split a along axis 1 
last_col = x_split[-1] 


mask = tf.greater(last_col, tf.constant(6)) 
cond = tf.where(mask, 
       tf.add(last_col, tf.constant(1)), # if true, add one 
       tf.add(last_col, tf.constant(-1)))# if false, minus one 

x_split = x_split[0:-1] 
x_split.append(cond) 
ans = tf.concat(1, x_split) 


with tf.Session() as sess: 
    sess.run(tf.global_variables_initializer()) 
    arr = np.array([[1, 2, 3, 4, 5], 
        [6, 7, 8, 9, 10]]) 
    the_ans = sess.run(ans, feed_dict={a: arr}) 
''' 
the_ans is 
[[ 1 2 3 4 4] 
[ 6 7 8 9 11]] 
'''