Project

General

Profile

Bug #20

g_rms uses incorrect masses when reference is a PDB/GRO file

Added by Erik Lindahl about 14 years ago. Updated over 13 years ago.

Status:
Closed
Priority:
Low
Category:
analysis tools
Target version:
Affected version - extra info:
Affected version:
Difficulty:
uncategorized
Close

Description

g_rms uses a massweighted cRMS by default (which isn't documented).

When the reference state is a TPR file the masses are set correctly, but when
using a PDB or GRO file they are guessed incorrectly - probably from the atom names.

IMHO, the proper action would be to not use massweighting unless we are certain masses are correct.

History

#1 Updated by Berk Hess about 14 years ago

g_rms should have a (documented) -mw option, like g_confrms,
which is turned on by default.

The mass guessing is a more general issue.
There is an atommass.dat library file which is used to guess
the masses from the names. For proteins this works pretty
well, but it can produce some incorrect masses for any other type of system.

So we should decide if should get rid of the atommass.dat altogether,
or use it everywhere, also for g_rms.

Berk.

#2 Updated by David van der Spoel over 13 years ago

Will fix using (optional) atommass.dat and tpr if present.

#3 Updated by David van der Spoel over 13 years ago

Added -mw flag to g_rms which sets all weights to 1, added documentation to the
header of the program. Added extra debug output (optional) to the routine that
actually reads the input file (read_tps_conf).

Also available in: Atom PDF