Python中的 numpy.divide()

numpy.divide(arr1, arr2, out = None, where = True, cast = 'same_kind', order = 'K', dtype = None) ：
第一个数组中的数组元素除以第二个元素中的元素（所有元素都发生在元素方面）。 arr1 和 arr2 必须具有相同的形状，并且 arr2 中的元素不能为零；否则会引发错误。

参数 ：

arr1 : [array_like]Input array or object which works as dividend.
arr2 : [array_like]Input array or object which works as divisor.
out : [ndarray, optional]Output array with same dimensions as Input array,
placed with result.
**kwargs : allows you to pass keyword variable length of argument to a function.
It is used when we want to handle named argument in a function.
where : [array_like, optional]True value means to calculate the universal
functions(ufunc) at that position, False value means to leave the
value in the output alone.

返回 ：

An array with arr1/arr2(element-wise) as elements of output array.

代码 1：arr1 除以 arr2 元素

# Python program explaining
# divide() function
import numpy as np
  
# input_array
arr1 = [2, 27, 2, 21, 23]
arr2 = [2, 3, 4, 5, 6]
print ("arr1         : ", arr1)
print ("arr2         : ", arr2)
  
# output_array
out = np.divide(arr1, arr2)
print ("\nOutput array : \n", out)

输出 ：

arr1         :  [2, 27, 2, 21, 23]
arr2         :  [2, 3, 4, 5, 6]

Output array : 
 [ 1.          9.          0.5         4.2         3.83333333]

代码 2 ： arr1 的元素除以除数

# Python program explaining
# divide() function
import numpy as np
  
# input_array
arr1 = [2, 27, 2, 21, 23]
divisor = 3
print ("arr1         : ", arr1)
  
# output_array
out = np.divide(arr1, divisor)
print ("\nOutput array : \n", out)

输出 ：

arr1         :  [2, 27, 2, 21, 23]

Output array : 
 [ 0.66666667  9.          0.66666667  7.          7.66666667]

代码 3：如果 arr2 的元素 = 0，则发出警告

# Python program explaining
# divide() function
import numpy as np
  
# input_array
arr1 = [2, 27, 2, 21, 23]
arr2 = [2, 3, 0, 5, 6]
print ("arr1         : ", arr1)
print ("arr2         : ", arr2)
  
# output_array
out = np.divide(arr1, arr2)
print ("\nOutput array : ", out)

输出 ：

arr1         :  [2, 27, 2, 21, 23]
arr2         :  [2, 3, 0, 5, 6]

Output array :  [ 1.          9.                 inf  4.2         3.83333333]
RuntimeWarning: divide by zero encountered in true_divide
  out = np.power(arr1, arr2)

参考 ：
https://docs.scipy.org/doc/numpy-1.13.0/reference/generated/numpy.divide.html
.