moveby (vecadd) command

[Hanif]

Dear TCL users

"moveby" is a command based on "vecadd", which is used to shift
molecular coordinates in VMD.
In the following part of the tcl code, moveby generates this error:

atomselect moveby: non-numeric in vector

I wonder how this issue can be handled. I need to use the values of
some variables in "mobeby" command.

Regards,

Hanif

for {set countx 1} {$countx <= $segnum} {incr countx} {
for {set county 1} {$county <= $segnum} {incr county} {
for {set countz 1} {$countz <= $segnum} {incr countz} {
set segid P$countx$county$countz
segment $segid {

set offx [expr $countx*$driftx]
set offy [expr $county*$drifty]
set offz [expr $countz*$driftz]

$fsfg moveby {$offx $offy $offz}
$fsfg writepdb fsfg_shift_temp.pdb
pdb fsfg_shift_temp.pdb
}

coordpdb fsfg_shift_temp.pdb $segid
}
}
}

[Gerald W. Lester]

On 7/31/11 11:09 AM, Hanif wrote:
> Dear TCL users
>
> "moveby" is a command based on "vecadd", which is used to shift

> molecular coordinates in VMD....

Neither "moveby" not "vecadd" are Tcl built in commands. I'm guessing that
they are furnished by your VMD program/package.

Most of us on this newsgroup do not use VMD (whatever that is) but use Tcl
for a variety of other tasks.

I suggest that you post the question to a VMD user's group or to whomever
offers VMD support.

That being said, does the following changes to your code make it work:

for {set countx 1} {$countx <= $segnum} {incr countx} {
for {set county 1} {$county <= $segnum} {incr county} {
for {set countz 1} {$countz <= $segnum} {incr countz} {
set segid P$countx$county$countz
segment $segid {

set offx [expr {$countx*$driftx}]
set offy [expr {$county*$drifty}]
set offz [expr {$countz*$driftz}]

$fsfg moveby [list $offx $offy $offz]

$fsfg writepdb fsfg_shift_temp.pdb
pdb fsfg_shift_temp.pdb
}

coordpdb fsfg_shift_temp.pdb $segid
}
}
}

--
+------------------------------------------------------------------------+
| Gerald W. Lester, President, KNG Consulting LLC |
| Email: Gerald...@kng-consulting.net |
+------------------------------------------------------------------------+

[Simon]

On 31/07/2011 17:09, Hanif wrote:
> Dear TCL users
>
> "moveby" is a command based on "vecadd", which is used to shift
> molecular coordinates in VMD.
> In the following part of the tcl code, moveby generates this error:
>
> atomselect moveby: non-numeric in vector
>

This doesn't look like a tcl error message. Having found this with
Google: http://www.ks.uiuc.edu/Research/vmd/vmd-1.3/ug/node206.html I
see that "vecadd" was an extension written to improve arithemetic
performance so you probably need to look at the extension code. Of
course it might simply be that you've called a function with an alpha
character rather than a digit.

Simon