recursion depth problem

[half.italian at gmail.com]

On Apr 22, 11:49 am, proctor <12cc... at gmail.com> wrote:
> hello,
>
> i have a small function which mimics binary counting.  it runs fine as
> long as the input is not too long, but if i give it input longer than
> 8 characters it gives
>
> RuntimeError: maximum recursion depth exceeded in cmp
>
> i'm not too sure what i am doing improperly.  is there really a lot of
> recursion in this code?
>
> ==================
>
> import sys
>
> def ch4(item, n=0):
>         if n < len(item):
>                 if item[n] == '0':
>                         item[n] = '1'
>                         print ''.join(item)
>                         ch4(item)
>                 elif item[n] == '1':
>                         item[n] = '0'
>                         ch4(item, n+1)
>
> ch4(list(sys.argv[1]))
>
> ==================
>
> this function expects input in the form of a string of zeros, like
> this:
>
> python test-bin.py 00000000
>
> and is expected to output a list of permutations like this:
>
> $ python test-bin.py 0000
> 1000
> 0100
> 1100
> 0010
> 1010
> 0110
> 1110
> 0001
> 1001
> 0101
> 1101
> 0011
> 1011
> 0111
> 1111
>
> thanks for all help!
>
> sincerely,
> proctor

If you just want to make it work as is....check

sys.setrecursionlimit()

~Sean