restrict the function input to be float32 NumPy array

Question

Is there a way to restrict the type of function input in python or I should always convert the input NumPy array to be float 32 array if I want?

I am trying to restrict the function input argument type to be a float 32 NumPy array. I have try something like below:

import numpy as np

def f(input : np.float32):
    return input*2

However, if I give an int NumPy array, the function is still work and return an int array.

Jithin Johnson · Accepted Answer · 2021-06-13 16:06:33Z

1

Read more about Python Annotations here PEP3107.

Annotations doesn't force the function to accept input as the specified type.

Access annotations by, print(f.__annotations__) in your case.

You can use yourlist.astype(np.float32) to force the list argument to be NumPy float32.

def f(input : np.float32)-> np.float32:
    return input.astype(np.float32)*2

answered Jun 13, 2021 at 15:46

Jithin Johnson

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