How to implement the ReLU function in Numpy

Question

I want to make a simple neural network which uses the ReLU function. Can someone give me a clue of how can I implement the function using numpy.

Answer 1

You can do it in much easier way:

def ReLU(x):
    return x * (x > 0)

def dReLU(x):
    return 1. * (x > 0)