From: Strahs, Dr. Daniel Bernard (
Date: Fri Jun 10 2016 - 23:20:51 CDT


I think your error is this; you executed catdcd within the VMD console and received the following message:

vmd > catdcd
wrong # args: should be "catdcdList dcdFileNames outFile indexFile stride"

Try to run catdcd outside of VMD in a Terminal window (found in your Utilities folder). For example, my VMD is installed in /usr/local, and catdcd is located in


If you execute catdcd in the Terminal window, you will get a help message which tells you how to execute the command. You'll find it far easier to do it this way rather than in VMD.

Dan Strahs

From: <> on behalf of Heather Boltz <>
Sent: Friday, June 10, 2016 11:05 PM
Subject: vmd-l: CatDCD refuses to work (mac)

Hi everyone,

I have parsed through the archive of previous conversations about catdcd, but I have yet to find an answer..

I am running VMD 1.9.2 on a mac and every time I submit a catdcd job (regardless of syntax), catdcdList is called. From what I understand, this is a command that just echos proper catdcd syntax. I have located catdcd within the plugin folder (subfolder bin) within the VMD content, but for some reason, VMD will not recognize catdcd as a standalone command.

I have tried uninstalling and reinstalling VMD (and older versions of VMD) to no success.

Thank you for your help!