## 
## Example script that sets the "User" data field with time varying values
## which can be used to color over time 
##

##
## load a fake "trajectory" by repeatedly loading the same PDB :-)
##
set file /Home/h2/johns/vmd/proteins/brH.pdb
if {[molinfo num] > 0} {
  mol delete all
}
mol new $file 
for {set i 0} {$i<20} {incr i} {
  mol addfile $file
}


##
## Make an atom selection, set the "User" fields for all atoms
## in the selection ("all" in this case since I'm too lazy to do
## something more interesting)
##
set numframes [molinfo top get numframes]
set sel [atomselect top "all"]
for {set i 0} {$i<$numframes} {incr i} {
  animate goto $i
  $sel frame $i
  puts "Setting User data for frame [$sel frame] ..."
  $sel set user $i
}
$sel delete

##
## change the "color by" and "trajectory" tab settings so that 
## the new color values, and start it animating...
##
mol modcolor 0 0 User
mol colupdate 0 0 1
mol scaleminmax 0 0 0.0 $numframes
animate forward