GMX-MDMAT(1)

NAME
gmx-mdmat - Calculate residue contact maps

SYNOPSIS

    gmx mdmat [-f [<.xtc/.trr/...>]] [-s [<.tpr/.gro/...>]] [-n [<.ndx>]]
              [-mean [<.xpm>]] [-frames [<.xpm>]] [-no [<.xvg>]]
              [-b <time>] [-e <time>] [-dt <time>] [-xvg <enum>]
              [-t <real>] [-nlevels <int>]

DESCRIPTION

gmx mdmat makes distance matrices consisting of the smallest distance between residue pairs. With -frames, these distance matrices can be stored in order to see differences in tertiary structure as a function of time. If you choose your options unwisely, this may generate a large output file. By default, only an averaged matrix over the whole trajectory is output. Also a count of the number of different atomic contacts between residues over the whole trajectory can be made. The output can be processed with gmx xpm2ps to make a PostScript (tm) plot.

OPTIONS

Options to specify input files:

-f [<.xtc/.trr/...>] (traj.xtc)
    Trajectory: xtc trr cpt gro g96 pdb tng h5md

-s [<.tpr/.gro/...>] (topol.tpr)
    Structure+mass(db): tpr gro g96 pdb brk ent

-n [<.ndx>] (index.ndx) (Optional)
    Index file

    Options to specify output files:

-mean [<.xpm>] (dm.xpm)
    X PixMap compatible matrix file

-frames [<.xpm>] (dmf.xpm) (Optional)
    X PixMap compatible matrix file

-no [<.xvg>] (num.xvg) (Optional)
    xvgr/xmgr file

    Other options:

-b <time> (0)
    Time of first frame to read from trajectory (default unit ps)

-e <time> (0)
    Time of last frame to read from trajectory (default unit ps)

-dt <time> (0)
    Only use frame when t MOD dt = first time (default unit ps)

-xvg <enum> (xmgrace)
    xvg plot formatting: xmgrace, xmgr, none

-t <real> (1.5)
    trunc distance

-nlevels <int> (40)
    Discretize distance in this number of levels

SEE ALSO

gmx(1)

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