How to set the return of a function to a variable in Python?

Question

This is another bit of my code that I posted in another question that has been giving me trouble.

I need to set the result of a function equal to a variable.

Let's say I have a function that divides pizza of x slices between y people.

def pizzaFunction(x,y):
    return x/y

Simple enough. But now say I need to print that into a statement later so that the statement says

print("The number of slices per person is",slice_number)

So my question is, since

slice_number = pizzaFunction(x,y)

does not work, is there another way to do this? It is important that it be saved into some variable so that it can be used in a print statment later.

Any and all help is appreciated.

The exact error I'm getting when I try the above method is

NameError: "name 'slice_number' is not defined"

http://stackoverflow.com/questions/750136/python-how-to-return-something-from-a-function-that-makes-a-dictionary — CodeMed, Dec 01 '13 at 06:59
@IsmailBadawi I wish I knew, but when I try I get the error "name 'slice_number' is not defined" — user2977230, Dec 01 '13 at 07:00
Are you doing `print("The number of slices per person is", slice_number = pizzaFunction(x,y))`? — Burhan Khalid, Dec 01 '13 at 07:01
Show us the non-working code. My guess is a scope error; you assigned to `slice_number` inside a function, expecting that assignment to affect a global `slice_number` variable instead of creating a local variable. — user2357112, Dec 01 '13 at 07:03
The non working code is much longer but is a homework assignment, and I feel I'd be cheating my class and my self if I got answers _too_ specific. The above code is a simple microcosm of my non-working code. Basically, the variable is set equal to a different function depending on which if-statement is true. — user2977230, Dec 01 '13 at 07:28

score 1 · Answer 1 · edited Dec 01 '13 at 07:10

1

How you're doing it seems to work fine.

Example:

def Pizza(x,y):
    return x/y

z = Pizza(12,3)

print("%i slices per person" % z)

Produces:

4 slices per person

edited Dec 01 '13 at 07:10

K DawG

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answered Dec 01 '13 at 07:01

MoJi

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Maybe it's because I have multiple functions that would return the same variable in an if/then series. So depending on which if statement is true, the function used changes. – user2977230 Dec 01 '13 at 07:07
@user2977230: "multiple functions that would return the same variable" - functions return objects, not variables. It doesn't matter what name a function uses to refer to the thing it returns; the code calling the function can't tell whether the return value used to be called `result` or `foo` or `roasted_walnuts`. I suggest you read up on the scope rules. – user2357112 Dec 01 '13 at 08:02

score 0 · Answer 2 · answered Dec 01 '13 at 07:13

I assume, "does not work" might refer to a integer division "error": Python might consider x as an integer, divides by y and returns the result as an integer as well (which means that all decimal digits are cut)

use return float(x)/y in your function.

If this is not the problem, I strongly assume a typo or indentation error in your code. Or you define your function after first usage.

How to set the return of a function to a variable in Python?

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