From: Francesco Pietra (chiendarret_at_gmail.com)
Date: Wed Nov 04 2020 - 04:46:42 CST

Solved
>Main< (MD) 54 % set restrainsel [atomselect top "index 1 to 21 5633 to
5649 5650 to 5671 11267 to 11288 11289 to 11309 16907 to 16922"]

---------- Forwarded message ---------
From: Francesco Pietra <chiendarret_at_gmail.com>
Date: Wed, Nov 4, 2020 at 11:36 AM
Subject: Restraining selected atoms with multimer
To: VMD Mailing List <vmd-l_at_ks.uiuc.edu>

Hello
I am trying to restrain selected atoms (actually selected residues) with a
homotrimer, where the residues belong to different chains.

It seems to me that the only route is through the index. However, I was
unable to set the correct syntax. For example

>Main< (MD) 52 % set restrainsel [atomselect top "index 1 to 21 and 5633
to 5649 and 5650 to 5671 and 11267 to 11288 and 11289 to 11309 and 16907 to
16922"]
atomselect: cannot parse selection text: index 1 to 21 and 5633 to 5649
and 5650 to 5671 and 11267 to 11288 and 11289 to 11309 and 16907 to 16922
>Main< (MD) 53 %

Although wrong, it is clear from the above what I would like to do (the
residues to restrain are where I cut the system to alleviate the
calculation)

Thanks for advice
francesco pietra