* This file is correl.inp.
* Usage, charmm <correl.inp >correl.out.
* Generates the chi1 and chi2 rotamer angle distributions in a trajectory.
* Requires on the order of 380 KB of memory.
*

! Open and read amino acid topology and parameter files
open read card name "top_all27_prot_na.rtf" unit 20
read rtf card unit 20
close unit 20

open read card name "par_all27_prot_na.prm" unit 20
read parameter card unit 20
close unit 20

! Open and read psf file
open read card name "fullprot.psf" unit 20
read psf card unit 20
close unit 20

open read unit 51 file name sim.dcd
trajectory query unit 51
open write unit 52 card name rotamer.tst

correl maxtime ?nfile maxseries 2 maxatoms 10 
enter chi1 dihe PROT 7 N PROT 7 CA PROT 7 CB PROT 7 CG geom
enter chi2 dihe PROT 7 CA PROT 7 CB PROT 7 CG PROT 7 OD1 geom
trajectory firstu 51 nunit 1 begin ?start stop ?nstep skip ?skip

write all unit 52 card
*angles
*

stop