i am starting to experiment with recursion, and decided to write a
fairly trivial little program which took a float as input, then called
a function to halve it recursively until it was less than 1:
____________________________________________________________________
import recursive_halve_module
raw_value = raw_input('please enter the number you would like to halve:
')
value = float(raw_value)
final_value = recursive_halve_module.recursive_halve(value)
print final_value
raw_input('hit enter to close: ')
_____________________________________________________________________
def recursive_halve(value):
if value < 1:
print value
return value
else:
value = value/2
print value
if value < 1:
return value
else:
recursive_halve(value)
______________________________________________________________________
it works fine apart from printing 'None' instead of 'final_value' at
the end. however, if you enter a value that is already less than 1, it
prints 'final_value' (i.e. that very same number) just fine.
now, it looks to me like only 'value' can be returned: either right at
the beginning (for values less than 1) or when you eventually get down
to below 1 after x function calls. but clearly that's not the case. i
understand that 'None' is returned by default by functions in Python.
my question is: how am i slipping into that default despite seemingly
(to me at least) avoiding it through explicitly returning something
else?
thanks in advance,
sam
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