g_rms(1)

NAME
g_rms VERSION 3.2.0

SYNOPSIS
g_rms -s topol.tpr -f traj.xtc -f2 traj.xtc -n index.ndx -o rmsd.xvg -mir rmsdmir.xvg -a avgrp.xvg -dist rmsd-dist.xvg -m rmsd.xpm -bin rmsd.dat -bm bond.xpm -[no]h -nice int -b time -e time -dt time -tu enum -[no]w -what enum -[no]pbc -fit enum -prev int -[no]split -skip int -skip2 int -max real -min real -bmax real -bmin real -nlevels int

DESCRIPTION
g_rms compares two structures by computing the root mean square deviation (RMSD), the size-independent 'rho' similarity parameter (rho) or the scaled rho (rhosc), see Maiorov & Crippen, PROTEINS 22 , 273 (1995). This is selected by -what Each structure from a trajectory ( -f ) is compared to a reference structure. The reference structure is taken from the structure file ( -s ). With option -mir also a comparison with the mirror image of the reference structure is calculated. This is useful as a reference for 'significant' values, see Maiorov & Crippen, PROTEINS 22 , 273 (1995). Option -prev produces the comparison with a previous frame the specified number of frames ago. Option -m produces a matrix in .xpm format of comparison values of each structure in the trajectory with respect to each other structure. This file can be visualized with for instance xv and can be converted to postscript with xpm2ps Option -fit controls the least-squares fitting of the structures on top of each other: complete fit (rotation and translation), translation only, or no fitting at all. With -f2 , the 'other structures' are taken from a second trajectory, this generates a comparison matrix of one trajectory versus the other. Option -bin does a binary dump of the comparison matrix. Option -bm produces a matrix of average bond angle deviations analogously to the -m option. Only bonds between atoms in the comparison group are considered.

FILES
-s topol.tpr Input
 Structure+mass(db): tpr tpb tpa gro g96 pdb xml -f traj.xtc Input
 Generic trajectory: xtc trr trj gro g96 pdb -f2 traj.xtc Input, Opt.
 Generic trajectory: xtc trr trj gro g96 pdb -n index.ndx Input, Opt.
 Index file -o rmsd.xvg Output
 xvgr/xmgr file -mir rmsdmir.xvg Output, Opt.
 xvgr/xmgr file -a avgrp.xvg Output, Opt.
 xvgr/xmgr file -dist rmsd-dist.xvg Output, Opt.
 xvgr/xmgr file -m rmsd.xpm Output, Opt.
 X PixMap compatible matrix file -bin rmsd.dat Output, Opt.
 Generic data file -bm bond.xpm Output, Opt.
 X PixMap compatible matrix file

OTHER OPTIONS
-[no]h no
 Print help info and quit -nice int 19
 Set the nicelevel -b time -1
 First frame (ps) to read from trajectory -e time -1
 Last frame (ps) to read from trajectory -dt time -1
 Only use frame when t MOD dt = first time (ps) -tu enum ps
 Time unit: ps , fs , ns , us , ms , s , m or h -[no]w no
 View output xvg, xpm, eps and pdb files -what enum rmsd
 Structural difference measure: rmsd , rho or rhosc -[no]pbc yes
 PBC check -fit enum rot+trans
 Fit to reference structure: rot+trans , translation or none -prev int 0
 Compare with previous frame -[no]split no
 Split graph where time is zero -skip int 1
 Only write every nr-th frame to matrix -skip2 int 1
 Only write every nr-th frame to matrix -max real -1
 Maximum level in comparison matrix -min real -1
 Minimum level in comparison matrix -bmax real -1
 Maximum level in bond angle matrix -bmin real -1
 Minimum level in bond angle matrix -nlevels int 80
 Number of levels in the matrices