From: Stefano Guglielmo (
Date: Sun Jan 29 2017 - 17:40:53 CST

Dear vmd users,

I am trying to calculate the energy of each frames of a trajectory
generated by NAMD in a metadynamics simulation; for this purpose I have
written the following tcl script:

package require bigdcd
proc metadynamics_energy { frame } {
     global all
     if {$frame == 1} {
     cv molid 0
     cv configfile ../colvar_grid.txt
     cv load ../cdk_8bS_pocket_metadyn_75ns_replica1
     cv update
     set energy [cv bias metadynamics1 energy]
     puts "$frame: $energy"
 set mol [mol new ../cdk2_8bS_pocket_wb_ion.psf type psf waitfor all]
 set all [atomselect $mol all]
 $all global
 bigdcd metadynamics_energy auto ../cdk_8bS_pocket_metadyn_75ns_replica1.dcd

When I source the script in vmd I got the following error message:

bigdcd aborting at frame 1
Error: total forces are currently not implemented.
Error loading state file
Info) VMD for LINUXAMD64, version 1.9.3 (November 30, 2016)
Info) Exiting normally.

Does anyone have suggestions?

Thanks in advance


Assistant Professor of Medicinal Chemistry
Department of Drug Science and Technology
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