检查两个numpy数组python中有多少元素相等

Question

I have two numpy arrays with number (Same length), and I want to count how many elements are equal between those two array (equal = same value and position in array)

A = [1, 2, 3, 4]
B = [1, 2, 4, 3]

then I want the return value to be 2 (just 1&2 are equal in position and value)

Answer 1

Using numpy.sum :

>>> import numpy as np
>>> a = np.array([1, 2, 3, 4])
>>> b = np.array([1, 2, 4, 3])
>>> np.sum(a == b)
2
>>> (a == b).sum()
2

Answer 2

只要两个阵列保证长度相同，您就可以使用：

np.count_nonzero(A==B)