Python – tensorflow.math.log_sigmoid()

TensorFlow 是由 Google 设计的开源Python库，用于开发机器学习模型和深度学习神经网络。 log_sigmoid()用于查找 x 的元素对数 sigmoid。具体来说，y = log(1 / (1 + exp(-x)))。

Syntax: tf.math.log_sigmoid(x, name)

Parameter:

• x: It’s the input tensor. Allowed dtype for this tensor are float32, float64.
• name(optional): It’s defines the name for the operation.

Returns:
It returns a tensor of same dtype as x.

示例 1：

Python3

# Importing the library
import tensorflow as tf
  
# Initializing the input tensor
a = tf.constant([.2, .5, .7, 1], dtype = tf.float64)
  
# Printing the input tensor
print('Input: ', a)
  
# Calculating result
res = tf.math.log_sigmoid(x = a)
  
# Printing the result
print('Result: ', res)

输出：

Input:  tf.Tensor([0.2 0.5 0.7 1. ], shape=(4, ), dtype=float64)
Result:  tf.Tensor([-0.59813887 -0.47407698 -0.40318605 -0.31326169], shape=(4, ), dtype=float64)

示例 2：可视化

Python3

# importing the library
import tensorflow as tf
import matplotlib.pyplot as plt
  
# Initializing the input tensor
a = tf.constant([.2, .5, .7, 1], dtype = tf.float64)
  
# Calculating result
res = tf.math.log_sigmoid(x = a)
  
# Plotting the graph
plt.plot(a, res, color = 'green')
plt.title('tensorflow.math.log_sigmoid')
plt.xlabel('Input')
plt.ylabel('Result')
plt.show()

输出：