Re: Iteration for Factorials

On Oct 22, 1:26 pm, Py-Fun <lorna.bu...@xxxxxxxxx> wrote:
I'm stuck trying to write a function that generates a factorial of a
number using iteration and not recursion. Any simple ideas would be
appreciated.

The following simple adder functions should give you an idea of how
recursion can be recast as iteration:

def acc(i):
'''i should be a positive integer'''
if i > 0:
return i + acc(i - 1)
return 0

print "acc", acc(9)

def itt(i):
'''i should be a positive integer'''
out = 0

while i > 0:
out += i
i = i - 1

return out

print "itt", itt(9)

...
Is it a "factorial" though?

Er, no. And neither is mine. You may want to google for the definition
of factorial! Here's a hint:

reduce(operator.mul, range(1, i + 1))

--
Anthony Roy


.

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