def sum10(a, b): if sum([a, b]) % 10 == 0: return True; return False print sum10(7, 3) print sum10(-13, -17) print sum10(3, 8) the result is:
True True None not what I expected:
True True False any idea?
Add a comment |
6 Answers
Your code
def sum10(a, b): if sum([a, b]) % 10 == 0: return True; return False is equivalent to
def sum10(a, b): if sum([a, b]) % 10 == 0: return True; return False so return False is never evaluated.
Some (of the probably endless) alternatives:
if sum([a, b]) % 10 == 0: return True return False or
return sum([a, b]) % 10 == 0 or
return True if sum([a, b]) % 10 == 0 else False or
return False if (a+b) % 10 else True or (the most readable IMHO)
return not (a + b) % 10 
This is what you want.
def sum10(a, b): return sum([a, b]) % 10 == 0 Also the ternary If in Python works like this
<True Statment> if <Conditional Expression> else <False Statement> eg
True if sum([a,b]) % 10 == 0 else False Might i also recommend using the plus operator?
True if (a+b) % 10 == 0 else False 
1 Comment
mko
Thanks for the ternary solution
If you want to have if-else one liners, they should be written like this:
return True if sum([a, b]) % 10 == 0 else False Note the absence of two points in that one liner.
1 Comment
mko
Thanks again for answering my question @alestanis, ternary is the way to go
I think that the return False is never executed due to it is into the if, not outside it.
So, when you take a true in the if condition, you are executing return True, but never the second statement.
1 Comment
mko
+1 for good explanation of what it doesn't work, I think I should stick to ternary way
def sum10(a, b): return sum([a, b])%10 == 0 
1 Comment
therealneil
Some explanation here would not go unappreciated.
Instead of returning True or False right away, you could try storing result in a boolean variable and then return that variable at the end. For example:
def sum(a,b): bool result if sum([a, b]) % 10 == 0: bool=True else: bool=False return bool 