From: John Stone (johns_at_ks.uiuc.edu)
Date: Mon Feb 06 2012 - 10:58:26 CST

It would seem that $ftemp is getting set to a non-numeric value.
Try adding a puts command in there to print $ftemp each time in the
foreach loop, and I suspect you'll find your problem.

Cheers,
  John Stone
  vmd_at_ks.uiuc.edu

On Mon, Feb 06, 2012 at 04:50:14PM +0000, Ban Arn wrote:
> Dear VMD Users
>
> I'm using following script
>
> foreach l [array names f] {
> set w($l) {}
> set fsum 0
> foreach ftemp $f($l) {
> set fsum [expr $fsum + $ftemp * $v * $dt]
> lappend w($l) $fsum
> }
> }
>
> for the calculation of work done for 10 simulations.
>
> While running the script it shows error as "missing operand at _@_
> in expression "0.25771 + _@_* 1 * 1"
>
> I'm not a tcl expert. Kinldy advice.
>
> Many Thanks
> Balaji

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