[gmx-users] all-atom pca

[gromacs query]

Hi All

I am doing PCA and its working fine if I choose few atoms only (heavy) and
I get extreme pdb file having heavy atoms for, say, eigenvector 1. But I
want to have extremes of all-atom structures, so I thought of doing PCA on
all-atoms but I end up with having Segmentation default error which I think
related to comp memory issue.
I think (please correct me) the extreme structures (heavy atoms) would
belong somewhere in the trajectory file. If I can get frame numbers of
these extremes calculated on heavy atoms then I can use same frame numbers
to dump all-atom structures. But how to get frame numbers for these
extremes? may be RMSD with respect to extremes on heavy atoms.

Thanks
Jio