How can I construct an if statement for numpy arrays' elements comparison, to produce a new array with same dimension?

import numpy as np


a = np.array([[3.5,6,8,2]])
b = np.array([[6,2,8,2]])
c = np.array([[2,3,7,5]])
d = np.array([[3,2,5,1]])
if a > b:
    e = 2*a+6*c
else:
    e = 3*c + 4*d

print(e)

then I got

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

and if I type in print(e), I got

[2, 3, 7, 5, 2, 3, 7, 5, 2, 3, 7, 5, 3, 2, 5, 1, 3, 2, 5, 1, 3, 2, 5, 1, 3, 2, 5, 1]

The e I want to construct is an array that has the same dimension with a,b,c,d , and the if statement that decides what equation will be used to make each element.

In other words, for the elements in of the first place of a and b: 3.5<6, so e = 3c + 4d = 32 + 43 = 18
For the second elements: 6>2, e = 2a+6c = 26 + 63 = 30

Third: 8=8, e = 3c + 4d = 37 + 45 = 41

Fourth: 2 = 2, e = 3c + 4d = 35 + 41 = 19

e = [18,30,41,19]

I tried to find someone who asked about constructing a script doing such things, but I could find none, and all numpy questions about if statement(or equivalent) did not help. Thanks.(It seems that a.all or a.any from the python recommendation did not help as well.)

>Solution :

Use numpy.where:

Return elements chosen from x or y depending on condition.

e = np.where(a > b, 2*a+6*c, 3*c + 4*d)