VMD-L Mailing List

From: Ajasja Ljubetič (ajasja.ljubetic_at_gmail.com)
Date: Thu Oct 28 2010 - 13:05:33 CDT

Dear Alex,

well, I can believe that (very) few people encounter this error.

I'm only worried about memory leaks. (But not that much, since I have at
most a few tens of such selections).
If the call $sel delete fails, then one would assume the selection remains
in memory. So does that mean then I could just skip the calls to $sel
delete?

Best regards,
Ajasja

On Thu, Oct 28, 2010 at 16:22, Axel Kohlmeyer <akohlmey_at_gmail.com> wrote:

> dear ajasja,
>
> On Thu, Oct 28, 2010 at 7:56 AM, Ajasja Ljubetič
> <ajasja.ljubetic_at_gmail.com> wrote:
> > Dear all,
> > I believe the following script should work, but it returns "can't unset
> > "upproc_var_atomselect23903": no such variable" .
>
> you are triggering an "undocumented feature" in VMD.
>
> if you want the long explanation and the code to remove
> the inconsistency in this behavior, you'll have to give me
> some time to dig it out of my private VMD tree. i've been
> proposing a couple of times to have this fixed, but it has
> been put on the backburner, since so extremely few people
> run into this issue, and the changes would require extensive
> testing to make sure no existing script/plugin is broken by it.
> since atom selections are such a key feature in VMD, the
> reluctance to apply this kind of change is very understandable.
>
> the short explanation is: don't worry. it is a side effect of
> $sel global and can be ignored. try replacing:
>
> $sel delete
>
> with:
>
> catch { $sel delete } msg
>
> and your code should work fine.
>
> cheers,
> axel.
>
>
> > Best regards,
> > Ajasja
> >
> >
> > proc freesel {sel} {
> > $sel delete
> > }
> > proc atest {sel} {
> > set a [atomselect top $sel]
> > $a global
> > return $a
> > }
> > proc dotest {} {
> > set selx [atest "protein"]
> > freesel $selx
> > }
> > dotest
>
>
>
> --
> Dr. Axel Kohlmeyer
> akohlmey_at_gmail.com http://goo.gl/1wk0
>
> Institute for Computational Molecular Science
> Temple University, Philadelphia PA, USA.
>