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From: Javier Montoya on 19 May 2010 11:29
On May 19, 4:06 pm, Steven D'Aprano <st...(a)REMOVE-THIS-
cybersource.com.au> wrote:
> On Wed, 19 May 2010 03:53:44 -0700, Javier Montoya wrote:
> > Dear all,
>
> > I've a list of float numbers and I would like to delete incrementally a
> > set of elements in a given range of indexes, sth. like:
>
> > for j in range(beginIndex, endIndex+1):
> >    print ("remove [%d] => val: %g" % (j, myList[j])) del myList[j]
>
> > However, since I'm iterating over the same list, the indexes (range) are
> > not valid any more for the new list. Does anybody has some suggestions
> > on how to delete the elements properly?
>
> Just delete the slice:
>
> del myList[beginIndex:endIndex+1]
>
> For small lists where you are deleting small chunks, this is the
> simplest, most straight-forward way.
>
> Alternatively, create a new list excluding the bits you would have
> deleted, and assign it in place:
>
> myList[:] = myList[:beginIndex] + myList[endIndex+1:]
>
> Note carefully that you aren't just re-binding the name "myList", but
> assigning to the slice myList[:].
>
> Then there is the old-fashioned way: iterate over the list backwards,
> deleting from the end towards the front.
>
> for j in range(endIndex, beginIndex-1, -1):
>     del myList[j]
>
> If your list is HUGE and you have very little memory, this is probably
> the least worst way. It might be slow, but it will work.
>
> Finally, we have this:
>
> myList[beginIndex:] = myList[endIndex+1:]
>
> --
> Steven

Hi guys,

A big thanks to everybody, it's amazing!

Cheers
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