问Python:如何检查是否可以添加两个数组？

EN

import numpy as np

A = np.array([[1, 1], [1, 2], [3, 1]])
B = np.array([[2, 3], [3, 2], [1, 4]])
C = np.array([[1, 2], [3, 4]])

# same shapes --> operations are not a problem
print(A+B)
print(A*B)

# shapes differ --> numpy raises ValueError
print(A+C)
print(A*C)

# prevent numpy raising an ValueError by prooving array's shapes manually before desired operation
def multiply(arr1, arr2):
    if arr1.shape == arr2.shape:
        return arr1 * arr2
    else:
        print('Shapes are not equal. Operation cannot be done.')

print(multiply(A, B))
print(multiply(A, C))

# prevent numpy raising an ValueError by prooving array's shapes manually before desired operation
def add(arr1, arr2):
    if arr1.shape == arr2.shape:
        return arr1 + arr2
    else:
        print('Shapes are not equal. Operation cannot be done.')

print(add(A, B))
print(add(A, C))


# catch the error / exception raised by numpy and handle it like you want to
try:
    result = A * C
except Exception as e:
    print('Numpy raised an Exception (ValueError) which was caught by try except.')
else:
    print(result)     

a = np.array([[1, 2], [3, 4], [5, 6]])
b = np.array([1, 2, 3])

a + b  # raises value error
np.broadcast(a, b)  # raise value error

a + b[:,None]   # does the addition with broadcasting
np.broadcast(a, b[:,None])   # returns a valid broadcast object