Python: How do I fix array of arrays returning none?

Question

This is my first post, and I am also new to programming, so I am sorry if I am doing anything atrociously wrong here.

I am trying to create a function that takes in an array and returns an array of arrays, with each inside array being two (or three) in length. (i.e. [1, 2, 3, 4, 5] returns [[1, 2], [3, 4, 5]])

Here is my code:

def split(array):
    newArray = []
    if len(array[0]) == 2:
        return array

    for i in range(len(array)):
        newArray.append(array[i][:len(array[i])//2])
        newArray.append(array[i][len(array[i])//2:])

    split(newArray)

array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
print(split([array]))

When I run it everything works fine until the return statement, which returns None, printing nothing (I was able to pinpoint the problem using PyCharm's debugger).

Is there something wrong with returning an array of arrays?

"returns none"... you didn't `return` the new array. – TigerhawkT3 Apr 26 '16 at 01:58 — TigerhawkT3, Apr 26 '16 at 01:58

score 2 · Accepted Answer · answered Apr 26 '16 at 01:59

You are missing a return statement at the end of your function:

def split(array):
    newArray = []
    if len(array[0]) == 2:
        return array

    for i in range(len(array)):
        newArray.append(array[i][:len(array[i])//2])
        newArray.append(array[i][len(array[i])//2:])

    return split(newArray) # return this

array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
print(split([array]))

>>> [[1, 2], [3, 4, 5], [6, 7], [8, 9, 10]]

Python: How do I fix array of arrays returning none?

1 Answers1