A little more: decimal_portion

[Chris Angelico]

On Sun, Oct 5, 2014 at 12:58 AM, Seymore4Head
<Seymore4Head at hotmail.invalid> wrote:
>  A little more: decimal_portion
>
> Write a function that takes two number parameters and returns a float
> that is the decimal portion of the result of dividing the first
> parameter by the second. (For example, if the parameters are 5 and 2,
> the result of 5/2 is 2.5, so the return value would be 0.5)
>
> http://imgur.com/a0Csi43
>
> def decimal_portion(a,b):
>     return float((b/a)-((b//a)))
>
> print (decimal_portion(5,2))
>
> I get 0.4 and the answer is supposed to be 0.5.

Work out exactly what your program is doing, step by step. Print out
the intermediate steps in the calculation, and compare what the
program's doing to what you expect to be happening. What's (b/a)?
What's (b//a)? What's (b/a)-((b//a))?

ChrisA