On 2006-07-18, guthrie <[EMAIL PROTECTED]> wrote:
> Beginner question! :-)
>
> x=[1,2,3,4]
> for i in range(len(x)):
> print x[:-i]
>
> >>> []
> >>> [1,2,3]
> >>> [1,2]
> >>> [1]
>
> 1) The x[:-0] result seems inconsistent to me;
> I get the idea that -0=0, so it is taken as x[:0] -> []
That is correct. Negative indexes are a handy shorthand, but
they can give unexpected/strange results in a number of cases.
> 2) how then should one do this basic left-recursive subsetting (easily).
x=[1,2,3,4]
lng = len(x)
for i in range(lng):
print x[:lng-i]
--
Antoon Pardon
--
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