python - While Trying to def: TypeError: unsupported operand type(s) for ** or pow(): 'NoneType' and 'int' -

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i using code in python 2.7 produce new number by:

def alg(n):     n=((n**2)-1)/4     return n

and error message:

typeerror: unsupported operand type(s) ** or pow(): 'nonetype' , 'int'

any great! thanks!

somehow, you're passing none when call function, what's happening:

alg(none)

... n none inside function, causing error. in other words: problem not in function, it's in point you're calling it.

also word of warning - you're performing division between integers, better play safe , make sure @ least 1 of division's operands decimal, or else loose precision:

def alg(n):               # there's no need reassign n     return ((n**2)-1)/4.0 # notice .0 part @ end

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