Hoi :) Maybe the following lines are useful. First, to extract the first model from a PDB file:
sed /ENDMDL/q trajectory.pdb > first.pdb Just for the record, to extract a specific frame # from a PDB file: sed -ne '{/^MODEL *# /,/ENDMDL/p}' trajectory.pdb > frame-#.pdb (NOTE: replace # with the number) Then, to extract the last frame from a PDB file: sed -ne '/^MODEL/,/^ENDMDL/{/^MODEL/{x;d};H}' -e '${x;p}' trajectory.pdb > last.pdb With these lines it does not matter whether the frames/models have equal (numbers of) atoms or not. Hope it helps, Tsjerk On Sat, Feb 12, 2011 at 10:09 AM, David van der Spoel <sp...@xray.bmc.uu.se> wrote: > On 2011-02-12 02.19, Mark Abraham wrote: >> >> On 12/02/2011 3:45 AM, Kwee Hong wrote: >>> >>> Hi Mark, >>> >>> I tried but with this error: >>> >>> Fatal error: >>> Number of atoms in pdb frame 0 is 331 instead of 491 >> >> OK. I don't know why two frames with different numbers of atoms are >> written. Maybe g_confrms -one is useful. Or you can chop apart the PDB >> by hand in a text editor. >> >> Mark >> >>> ------------------------------------------------------------------------ >>> *From:* Mark Abraham <mark.abra...@anu.edu.au> >>> *To:* Discussion list for GROMACS users <gmx-users@gromacs.org> >>> *Sent:* Saturday, February 12, 2011 0:01:39 >>> *Subject:* Re: [gmx-users] doubts on g_confrms output >>> >>> On 12/02/2011 2:55 AM, Kwee Hong wrote: >>>> >>>> Hi Tsjerk, >>>> >>>> Thanks for the help. I got it. >>>> But do you have any idea how to solve this in vmd? >>> >>> Use trjconv -sep on the .pdb file to split it. >>> >>> Mark >>> >>>> >>>> Regards, >>>> Joyce >>>> >>>> ------------------------------------------------------------------------ >>>> *From:* Tsjerk Wassenaar <tsje...@gmail.com> >>>> *To:* Discussion list for GROMACS users <gmx-users@gromacs.org> >>>> *Sent:* Saturday, January 22, 2011 15:53:22 >>>> *Subject:* Re: [gmx-users] doubts on g_confrms output >>>> >>>> Hi Joyce, >>>> >>>> In pymol use 'set all_states' >>>> >>>> Cheers, >>>> >>>> Tsjerk >>>> >>>>> On Jan 22, 2011 8:30 AM, "Kwee Hong" <jestan1...@yahoo.com >>>>> <mailto:jestan1...@yahoo.com>> wrote: >>>>> >>>>> Hi, >>>>> >>>>> I was trying to do some analysis following John's "GROMACS tutorial >>>>> for solvation study of spider toxin peptide". >>>>> I'm using GROMACS-4.5.3 and my command line for g_confrms is >>>>> >>>>> g_confrms -f1 1OMB.pdb -f2 md.gro -o fit_wet.pdb >>>>> > > If e.g. 1OMB.pdb does not have hydrogen and md.gro does, you need to specify > two index files, pointint to e.g. the C-alpha atoms. Then the fit can be > done on these and your superposition will be fine. > > >>>>> The program calculated the RMSD sucessfully and fit_wet.pdb was >>>>> generated. Yet, when i tried to visualise fit_wet.pdb using VMD, the >>>>> structure is obviously in a mess. And when I tried it out with >>>>> pymol, I can only visualised one model. Model 2 did not appear. I >>>>> wonder would it be the pdb format generated by g_confrms is not the >>>>> standard pdb format and had caused VMD and final failed to read them? >>>>> >>>>> Herein, I attached part of the pdb file generated by fit_wet.pdb. >>>>> Any insight is welcomed. >>>>> >>>>> Thanks, >>>>> Joyce >>>>> >>>>> >>>>> >>>>> -- >>>>> gmx-users mailing list gmx-users@gromacs.org >>>>> <mailto:gmx-users@gromacs.org> >>>>> http://lists.gromacs.org/mailman/listinfo/gmx-users >>>>> 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-requ...@gromacs.org >>>>> <mailto:gmx-users-requ...@gromacs.org>. >>>>> Can't post? Read http://www.gromacs.org/Support/Mailing_Lists >>>> >>> >>> >> > > > -- > David van der Spoel, Ph.D., Professor of Biology > Dept. of Cell & Molec. Biol., Uppsala University. > Box 596, 75124 Uppsala, Sweden. Phone: +46184714205. > sp...@xray.bmc.uu.se http://folding.bmc.uu.se > -- > gmx-users mailing list gmx-users@gromacs.org > http://lists.gromacs.org/mailman/listinfo/gmx-users > 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-requ...@gromacs.org. > Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > -- Tsjerk A. Wassenaar, Ph.D. post-doctoral researcher Molecular Dynamics Group * Groningen Institute for Biomolecular Research and Biotechnology * Zernike Institute for Advanced Materials University of Groningen The Netherlands -- gmx-users mailing list gmx-users@gromacs.org http://lists.gromacs.org/mailman/listinfo/gmx-users 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-requ...@gromacs.org. Can't post? Read http://www.gromacs.org/Support/Mailing_Lists