[Tutor] Calculate 4**9 without using **

[Alex Kleider]

On 2017-03-05 23:52, Sri Kavi wrote:



> This version deals with both negative and non-negative exponents in a
> single loop. I like this.
> def power(base, exponent):
>     """ Returns base**exponent. """
>     if exponent == 0:
>         return 1
>     else:
>         result = 1
>         for _ in range(abs(exponent)):
>             result *= base
>         if exponent < 0:
>             return 1 / result
>         else:
>             return result
> 
> I'm learning a lot. Thank you for being so helpful.

I have enjoyed this little exercise, so thank you for drawing attention 
to it and continuing to work at it.
Note that you don't need the 1st if/else- and even if you did, you 
wouldn't need the 'else': just 'de-iondent' everything that is in its 
code block.
I believe the following (your code with some deletions) will work:

def power(base, exponent):
     """ Returns base**exponent. """
     result = 1
     for _ in range(abs(exponent)):
         result *= base
     if exponent < 0:
         return 1 / result
     else:
         return result

An alternative way to deal with the negative exponent possibility is to 
test for it at the beginning and if True, set base to its reciprocal and 
exponent to its absolute value (no need for an else component.)