From: Prathit Chatterjee (
Date: Thu Jun 04 2020 - 01:37:54 CDT

Dear VMD experts,

This is regarding selecting selected characters of a variable with tcl scripting in VMD.
I want to select first few characters of a variable, for example, first three characters (app) of the variable "apple":
vmd > set a apple
vmd > string length $a

I am trying to play around with the command string but could not figure out so far.

Any relevant comments/suggestions will be greatly appreciated.
Thank you in advance,