numpy count_nonzero 方法 | Python

numpy.count_nonzero()函数计算数组 arr 中非零值的数量。

Syntax : numpy.count_nonzero(arr, axis=None)

Parameters :
arr : [array_like] The array for which to count non-zeros.
axis : [int or tuple, optional] Axis or tuple of axes along which to count non-zeros. Default is None, meaning that non-zeros will be counted along a flattened version of arr.

Return : [int or array of int] Number of non-zero values in the array along a given axis. Otherwise, the total number of non-zero values in the array is returned.

代码#1：

# Python program explaining
# numpy.count_nonzero() function
  
# importing numpy as geek 
import numpy as geek
  
arr = [[0, 1, 2, 3, 0], [0, 5, 6, 0, 7]]
  
gfg = geek.count_nonzero(arr)
  
print (gfg) 

输出 ：

6

代码#2：

# Python program explaining
# numpy.count_nonzero() function
  
# importing numpy as geek 
import numpy as geek
  
arr = [[0, 1, 2, 3, 4], [5, 0, 6, 0, 7]]
  
gfg = geek.count_nonzero(arr, axis = 0)
  
print (gfg) 

输出 ：

7