Python中的 numpy.alen()

numpy.alen()函数用于返回输入数组第一维的长度。

Syntax : numpy.alen(arr)

Parameters :
arr : [array_like] Input array.

Return : [int]Length of the first dimension of arr.

代码#1：

# Python program explaining
# alen() function
   
import numpy as geek
  
# input array(2 * 3)
in_arr = geek.array([[ 2, 0, 7], [ 0, 5, 9]])
print ("Input array : ", in_arr) 
  
out_dim = geek.alen(in_arr)
print ("Length of the first dimension of arr: ", out_dim)

输出：

Input array :  [[2, 0, 7], [0, 5, 9]]
Length of the first dimension of arr:  2

代码#2：

# Python program explaining
# alen() function
   
import numpy as geek
  
# input array(1 * 3*3)
in_arr = geek.arange(9).reshape(1, 3, 3)
print ("Input array : \n", in_arr) 
  
out_dim = geek.alen(in_arr)
print ("Length of the first dimension of arr: ", out_dim)

输出：

Input array : 
 [[[0 1 2]
  [3 4 5]
  [6 7 8]]]
Length of the first dimension of arr:  1