On May 9, 7:49 pm, Charles Sanders <[EMAIL PROTECTED]>
wrote:
> [EMAIL PROTECTED] wrote:
> > On May 9, 1:13 am, Charles Sanders <[EMAIL PROTECTED]>
> > wrote:
> [snip]
> >> or even this monstrosity ...
>
> >> def permute2( s, n ):
> >> return [ ''.join([ s[int(i/len(s)**j)%len(s)]
> >> for j in range(n-1,-1,-1)])
> >> for i in range(len(s)**n) ]
>
> >> print "permute2('abc',2) =", permute2('abc',2)
> >> print "len(permute2('13579',3)) =", len(permute2('13579',3))
>
> >> permute2('abc',2) = ['aa', 'ab', 'ac', 'ba', 'bb', 'bc',
> >> 'ca', 'cb', 'cc']
> >> len(permute2('13579',3)) = 125
>
> >> Charles
>
> > Could you explain, this one, actually? Don't forget StopIteration.
>
> As Michael said, simple counting in base n with the
> string as the digits. No attempt at clarity or efficiency (I
> did say it was a "monstrosity").
>
> Also, as a python beginner I didn't know about divmod,
> and have no idea what you (castironpi) mean by "Don't forget
> StopIteration."
>
> Charles
Please disregard. I have just learned that:
"If the generator exits without yielding another value, a
StopIteration exception is raised."
"exception StopIteration
Raised by an iterator's next() method to signal that there are no
further values."
Means normal generator termination.
--
http://mail.python.org/mailman/listinfo/python-list
