Jaggo wrote:
> Hello!
>
> I desperately need a simple way to compare whether any item of SmallList
> is in BigList.
>
> My current way,
>
> def IsAPartOfList(SmallList,BigList)
> for item in SmallList:
> if item in BigList:
> return True
> return False
>
> Takes up waay too much time to process.
> Can anyone think of any better way?
>
> Usually, SmallList is generated using range(Long, Long+ ~300)
> BigList is usually of a few hundreds of long numbers.
Why not just check if if any item in BigList is in the range Long, Long+300?
for item in BigList:
if Long < item <= Long+300:
return True
return False
which (in Python 2.5) can be shortened to
return any(item in BigList if if Long < item <= Long+300)
If you really have to make the list, you will do better with a set,
especially if the set can be reused over multiple calls.
bigSet = set(BigList)
return any(item for item in SmallList if item in BigList)
If speed is critical, you might see if it matters which list becomes the
set and which is iterated.
Kent
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