man g_traj (Commandes) - g_traj VERSION 3.3_beta_20050823

NAME

g_traj VERSION 3.3_beta_20050823

SYNOPSIS

g_traj -f traj.xtc -s topol.tpr -n index.ndx -ox coord.xvg -ov veloc.xvg -of force.xvg -ob box.xvg -ot temp.xvg -ekt ektrans.xvg -ekr ekrot.xvg -vd veldist.xvg -cv veloc.pdb -cf force.pdb -[no]h -nice int -b time -e time -dt time -tu enum -[no]w -[no]xvgr -[no]com -[no]mol -[no]nojump -[no]x -[no]y -[no]z -ng int -[no]len -bin real -scale real

DESCRIPTION

g_traj plots coordinates, velocities, forces and/or the box. With -com the coordinates, velocities and forces are calculated for the center of mass of each group. When -mol is set, the numbers in the index file are interpreted as molecule numbers and the same procedure as with

-com is used for each molecule.

Option -ot plots the temperature of each group, provided velocities are present in the trajectory file. No corrections are made for constrained degrees of freedom! This implies -com

Options -ekt and -ekr plot the translational and rotational kinetic energy of each group, provided velocities are present in the trajectory file. This implies -com

Options -cv and -cf write the average velocities and average forces as temperature factors to a pdb file with the average coordinates. The temperature factors are scaled such that the maximum is 10. The scaling can be changed with the option

-scale frame set both -b and -e to the time of desired frame. When averaging over frames you might need to use the -nojump option to obtain the correct average coordinates.

Option -vd computes a velocity distribution, i.e. the norm of the vector is plotted. In addition in the same graph the kinetic energy distribution is given.

FILES

-f traj.xtc Input Generic trajectory: xtc trr trj gro g96 pdb

-s topol.tpr Input Structure+mass(db): tpr tpb tpa gro g96 pdb xml

-n index.ndx Input, Opt. Index file

-ox coord.xvg Output, Opt. xvgr/xmgr file

-ov veloc.xvg Output, Opt. xvgr/xmgr file

-of force.xvg Output, Opt. xvgr/xmgr file

-ob box.xvg Output, Opt. xvgr/xmgr file

-ot temp.xvg Output, Opt. xvgr/xmgr file

-ekt ektrans.xvg Output, Opt. xvgr/xmgr file

-ekr ekrot.xvg Output, Opt. xvgr/xmgr file

-vd veldist.xvg Output, Opt. xvgr/xmgr file

-cv veloc.pdb Output, Opt. Protein data bank file

-cf force.pdb Output, Opt. Protein data bank file

OTHER OPTIONS

-[no]h no Print help info and quit

-nice int 19 Set the nicelevel

-b time 0 First frame (ps) to read from trajectory

-e time 0 Last frame (ps) to read from trajectory

-dt time 0 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

-[no]xvgr yes Add specific codes (legends etc.) in the output xvg files for the xmgrace program

-[no]com no Plot data for the com of each group

-[no]mol no Index contains molecule numbers iso atom numbers

-[no]nojump no Remove jumps of atoms across the box

-[no]x yes Plot X-component

-[no]y yes Plot Y-component

-[no]z yes Plot Z-component

-ng int 1 Number of groups to consider

-[no]len no Plot vector length

-bin real 1 Binwidth for velocity histogram (nm/ps)

-scale real 0 Scale factor for pdb output, 0 is autoscale

SEE ALSO

gromacs(7)

More information about the GROMACS suite is available in /usr/share/doc/gromacs or at <http://www.gromacs.org/>.