[gmx-users] Indexing problem when using genconf
Ryan S Davis (rsdavis1)
rsdavis1 at memphis.edu
Tue May 31 05:12:15 CEST 2011
I wanted to copy a bilayer into a grid of 2x2x1 replicas. I used genconf and everything seemed to work fine exept that annoying feature
that the command does not reorder the molecule types, so I end up with a .top file looking like this...
1 #include "martini_v2.1.itp"
2 #include "martini_v2.0_lipids.itp"
3 #include "martini_v2.0_cholesterol.itp"
5 [ system ]
8 [ molecules ]
9 DPPC 832
10 CHOL 208
11 W 8320
12 DPPC 832
13 CHOL 208
14 W 8320
15 DPPC 832
16 CHOL 208
17 W 8320
18 DPPC 832
19 CHOL 208
20 W 8320
Anyway, I run the simulation...no errors. I make an ndx file using make_ndx...indices look fine despite the repetitive order. HOWEVER, when I try to run commands such as
trjconv with the index file as input, it reads all the way up to the first block of Waters and quits with the error
Program trjconv, VERSION 4.0.7
Source code file: gmx_trjconv.c, line: 1037
Index 46593 is larger than the number of atoms in the trajectory file (46592)
which I didnt expect, but makes perfect sense knowing that I specified in the .mdp file to not output water to the xtc file...
xtc-grps = dppc chol
Normally this isnt an issue because waters are typically last in the topology. But, I still need access to this data. How can I force the post-processing commands to read past the absent water blocks?
The only options I see at the moments is to
1) scrap genconf, make new topology somehow, and rerun
2) reset to output water, and rerun
3) limit my analysis to the very sparse output from the .trr file
Thanks for any suggestions,
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