check how many elements are equal in two numpy arrays python
PythonArraysNumpyPython Problem Overview
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)
Python Solutions
Solution 1 - Python
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
Solution 2 - Python
As long as both arrays are guaranteed to have the same length, you can do it with:
np.count_nonzero(A==B)