[gmx-users] nan in g_anaeig -over

Mark Abraham Mark.Abraham at anu.edu.au
Thu Jul 26 17:48:02 CEST 2012


On 27/07/2012 12:31 AM, Joaquim Rui de Castro Rodrigues wrote:
> Dear all,
>   
> I am getting a nan while calculating the overlap between covariance matrices (in this case, using the same vectors for -v and -v2):
> g_anaeig455 -v atp/eigenvectors.trr -v2 atp/eigenvectors.trr -over overlap_atp-atp
>   
> I tried different gromacs versions, different -last values, and also setting the -eig and -eig2 flags, with the same results.
> Any idea what could be wrong here?
> Please find below the content of the .xvg file and the ouput from g_anaeig.
>   
> Thanks for your time,
> Rui Rodrigues
>   
>   
>   
> Here is the content of overlap_atp-atp.xvg:
> @    title "Subspace overlap"
> @    xaxis  label "Eigenvectors of trajectory 2"
> @    yaxis  label "Overlap"
> @TYPE xy
> @ subtitle "using 8 eigenvectors of trajectory 1"
>      1  0.125
>      2  0.250
>      3  0.375
>      4  0.500
>      5  0.625
>      6  0.750
>      7  0.875
>      8  1.000
>      9  1.000
>     10  1.000
> (...)
> 13586  1.000
> 13587  1.000
> 13588    nan
> 13589    nan
> 13590    nan
> (...)
> 13799    nan
> 13800    nan
>
>   
> Here is the complete ouput from g_anaeig:
>                           :-)  G  R  O  M  A  C  S  (-:
>                                S  C  A  M  O  R  G
>                              :-)  VERSION 4.5.5  (-:
>          Written by Emile Apol, Rossen Apostolov, Herman J.C. Berendsen,
>        Aldert van Buuren, Pär Bjelkmar, Rudi van Drunen, Anton Feenstra,
>          Gerrit Groenhof, Peter Kasson, Per Larsson, Pieter Meulenhoff,
>             Teemu Murtola, Szilard Pall, Sander Pronk, Roland Schulz,
>                  Michael Shirts, Alfons Sijbers, Peter Tieleman,
>                 Berk Hess, David van der Spoel, and Erik Lindahl.
>         Copyright (c) 1991-2000, University of Groningen, The Netherlands.
>              Copyright (c) 2001-2010, The GROMACS development team at
>          Uppsala University & The Royal Institute of Technology, Sweden.
>              check out http://www.gromacs.org for more information.
>           This program is free software; you can redistribute it and/or
>            modify it under the terms of the GNU General Public License
>           as published by the Free Software Foundation; either version 2
>               of the License, or (at your option) any later version.
>                  :-)  /usr/local/gromacs455/bin/g_anaeig455  (-:
> Option     Filename  Type         Description
> ------------------------------------------------------------
>    -v atp/eigenvectors.trr  Input        Full precision trajectory: trr trj cpt
>   -v2 atp/eigenvectors.trr  Input, Opt!  Full precision trajectory: trr trj cpt
>    -f       traj.xtc  Input, Opt.  Trajectory: xtc trr trj gro g96 pdb cpt
>    -s      topol.tpr  Input, Opt.  Structure+mass(db): tpr tpb tpa gro g96 pdb
>    -n      index.ndx  Input, Opt.  Index file
> -eig   eigenval.xvg  Input, Opt.  xvgr/xmgr file
> -eig2 eigenval2.xvg  Input, Opt.  xvgr/xmgr file
> -comp   eigcomp.xvg  Output, Opt. xvgr/xmgr file
> -rmsf   eigrmsf.xvg  Output, Opt. xvgr/xmgr file
> -proj      proj.xvg  Output, Opt. xvgr/xmgr file
>   -2d     2dproj.xvg  Output, Opt. xvgr/xmgr file
>   -3d     3dproj.pdb  Output, Opt. Structure file: gro g96 pdb etc.
> -filt  filtered.xtc  Output, Opt. Trajectory: xtc trr trj gro g96 pdb cpt
> -extr   extreme.pdb  Output, Opt. Trajectory: xtc trr trj gro g96 pdb cpt
> -overoverlap_atp-atp.xvg  Output, Opt! xvgr/xmgr file
> -inpr    inprod.xpm  Output, Opt. X PixMap compatible matrix file
> Option       Type   Value   Description
> ------------------------------------------------------
> -[no]h       bool   no      Print help info and quit
> -[no]version bool   no      Print version 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: fs, ps, ns, us, ms or s
> -[no]w       bool   no      View output .xvg, .xpm, .eps and .pdb files
> -xvg         enum   xmgrace  xvg plot formatting: xmgrace, xmgr or none
> -first       int    1       First eigenvector for analysis (-1 is select)
> -last        int    8       Last eigenvector for analysis (-1 is till the
>                              last)
> -skip        int    1       Only analyse every nr-th frame
> -max         real   0       Maximum for projection of the eigenvector on the
>                              average structure, max=0 gives the extremes
> -nframes     int    2       Number of frames for the extremes output
> -[no]split   bool   no      Split eigenvector projections where time is zero
> -[no]entropy bool   no      Compute entropy according to the Quasiharmonic
>                              formula or Schlitter's method.
> -temp        real   298.15  Temperature for entropy calculations
> -nevskip     int    6       Number of eigenvalues to skip when computing the
>                              entropy due to the quasi harmonic approximation.
>                              When you do a rotational and/or translational fit
>                              prior to the covariance analysis, you get 3 or 6
>                              eigenvalues that are very close to zero, and
>                              which should not be taken into account when
>                              computing the entropy.
> trn version: GMX_trn_file (single precision)
> Read non mass weighted reference structure with 4600 atoms from atp/eigenvectors.trr
> Read non mass weighted average/minimum structure with 4600 atoms from atp/eigenvectors.trr
> Read 13800 eigenvectors (for 4600 atoms)
> Read non mass weighted reference structure with 4600 atoms from atp/eigenvectors.trr
> Read non mass weighted average/minimum structure with 4600 atoms from atp/eigenvectors.trr
> Read 13800 eigenvectors (for 4600 atoms)
> 8 eigenvectors selected for output: 1 2 3 4 5 6 7 8
> Calculating overlap between eigenvectors of set 2 with eigenvectors
> 1 2 3 4 5 6 7 8
> RMSD (without fit) between the two average structures: 0.000 (nm)
> Will compare the covariance matrices using 13800 dimensions
> Trace of the two matrices: 339.752 and 339.752
> Square root of the traces: 18.4324 and 18.4324
> The overlap of the covariance matrices:
>    normalized:  nan
>         shape:  nan
> gcq#97: "The Universe is Somewhere In Here" (J.G.E.M. Fraaije)--
> gmx-users mailing list    gmx-users at gromacs.org
> http://lists.gromacs.org/mailman/listinfo/gmx-users
> * Only plain text messages are allowed!
> * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/Search before posting!
> * Please don't post (un)subscribe requests to the list. Use the
> www interface or send it to gmx-users-request at gromacs.org.
> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists

Something's wrong with your eigenvectors. Look at the other output files 
and/or gmxdump the eigenvector files.

Mark



More information about the gromacs.org_gmx-users mailing list