SYNOPSIS

gmx distance [-f [<.xtc/.trr/...>]] [-s [<.tpr/.tpb/...>]]

             [-n [<.ndx>]] [-oav [<.xvg>]] [-oall [<.xvg>]]
             [-oxyz [<.xvg>]] [-oh [<.xvg>]] [-oallstat [<.xvg>]]
             [-b <time>] [-e <time>] [-dt <time>] [-tu <enum>]
             [-xvg <enum>] [-[no]rmpbc] [-[no]pbc] [-sf <file>]
             [-selrpos <enum>] [-select <selection>] [-len <real>]
             [-tol <real>] [-binw <real>]

DESCRIPTION

gmx distance calculates distances between pairs of positions as a function of time. Each selection specifies an independent set of distances to calculate. Each selection should consist of pairs of positions, and the distances are computed between positions 1-2, 3-4, etc.

-oav writes the average distance as a function of time for each selection. -oall writes all the individual distances. -oxyz does the same, but the x, y, and z components of the distance are written instead of the norm. -oh writes a histogram of the distances for each selection. The location of the histogram is set with -len and -tol. Bin width is set with -binw. -oallstat writes out the average and standard deviation for each individual distance, calculated over the frames.

OPTIONS

Options to specify input and output files:

-f [<.xtc/.trr/...>] (traj.xtc) (Input, Optional)

    Input trajectory or single configuration: xtc trr cpt trj gro g96 pdb tng

-s [<.tpr/.tpb/...>] (topol.tpr) (Input, Optional)

    Input structure: tpr tpb tpa gro g96 pdb brk ent

-n [<.ndx>] (index.ndx) (Input, Optional)

    Extra index groups

-oav [<.xvg>] (distave.xvg) (Output, Optional)

    Average distances as function of time

-oall [<.xvg>] (dist.xvg) (Output, Optional)

    All distances as function of time

-oxyz [<.xvg>] (distxyz.xvg) (Output, Optional)

    Distance components as function of time

-oh [<.xvg>] (disthist.xvg) (Output, Optional)

    Histogram of the distances

-oallstat [<.xvg>] (diststat.xvg) (Output, Optional)

    Statistics for individual distances

Other options:

-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 if t MOD dt == first time (ps)

-tu <enum> (ps)

    Unit for time values: fs, ps, ns, us, ms, s

-xvg <enum> (xmgrace)

    Plot formatting: none, xmgrace, xmgr

-[no]rmpbc (yes)

    Make molecules whole for each frame

-[no]pbc (yes)

    Use periodic boundary conditions for distance calculation

-sf <file>

    Provide selections from files

-selrpos <enum> (atom)

    Selection reference positions: atom, res_com, res_cog, mol_com, mol_cog, whole_res_com, whole_res_cog, whole_mol_com, whole_mol_cog, part_res_com, part_res_cog, part_mol_com, part_mol_cog, dyn_res_com, dyn_res_cog, dyn_mol_com, dyn_mol_cog

-select <selection>

    Position pairs to calculate distances for

-len <real> (0.1)

    Mean distance for histogramming

-tol <real> (1)

    Width of full distribution as fraction of -len

-binw <real> (0.001)

    Bin width for histogramming

RELATED TO g_dist…

gromacs(7)

More information about GROMACS is available at <http://www.gromacs.org/>.