From: Eashan C (
Date: Fri Nov 20 2020 - 23:17:00 CST


I’ve only recently been introduced to VMD/NAMD and am currently trying to
work my way through the tutorials.

I keep running into errors with regards to either the parameters given in
the attached example files, or arithmetic operations across dcd files.

The most recent error I’ve been baffled by is an error while calculating
the average dipole moment across all frames of a simulation for a nanopore
in the Bionanotechnology Tutorial.

I keep getting an error along the lines of :

Can’t use non-numeric floating point value as an operand of ‘-‘

Unfortunately I don’t have a lot of computational processing experience nor
am I well versed with code, I’ve been able to figure out the errors that
have cropped up so far by going into the parameter files and tweaking
values, I don’t have the luxury to do so with this error.

My main question would be as to how to approach this particular problem.

Secondly I wanted to confirm the compatibility of the tutorial files
provided with the newer versions of VMD/NAMD

Thanks and Regards
Eashan Chopde
Undergrad, BITS Pilani

Eashan Chopde
Department of Sponsorship & Marketing
BITS Pilani,