[gmx-users] how to use the trjconv -sep and -skip to get the individual file

[aixintiankong]

Dear,
      I have made a 10ns prodution MD, The set  dt=0.002，nstxtcout   = 500 in mdp file.   I have made 10ns prodution MD, I want to extract frames from the molecular dynamics simulations at regular intervals of 10ps and keep the file as individual pdb file   i want to use the follow command ,
           trjconv -s topol.tpr -f traj.xtc -skip (number) -o conf.pdb -sep
but i don't now how to set the number of skip,please help me and tell me what the skip mean
thank you !