Is this an ideal way to automate object instantiation using functions?

Question

I'm trying to design a function in Python which instantiates a number of objects based on a user input. I've derived one which works, and it looks as follows

class Node(): ...

def initialise():
    binary_tree=[]
    opt=int(input("Enter the number of nodes you want\n"))
    for i in range(opt):
        a=Node()
        binary_tree.append(a)

although I'm not sure that this is the ideal way to do this.

Is there a better way of programming a function such as the one I've described, or is the above method sufficient for efficiency and clarity purposes?

Any responses are appreciated, thank you in advance.

You don't need to assign `Node` to `a`. Just directly do `binary_tree.append(Node())` — Chris, Feb 27 '19 at 08:13
Possible duplicate of [Create an empty list in python with certain size](https://stackoverflow.com/questions/10712002/create-an-empty-list-in-python-with-certain-size) — D Malan, Feb 27 '19 at 08:31

score 0 · Answer 1 · answered Feb 27 '19 at 09:27

Your code seems to work ok.

There are other options to format it; for example, you could use list comprehension, which might be slightly faster than using .append() and also uses slightly less code:

def initialise():
    opt = int(input("Enter the number of nodes you want\n"))

    return [
        Node()
        for _ in range(opt)]

Careful: this (as well as your version) code might raise a ValueError if the uses enters a string that cannot be converted to int.

Is this an ideal way to automate object instantiation using functions?

1 Answers1