Cannot select residues with names starting with numbers

[cmwoodley]

Just something I noticed when processing an example MD trajectory from the gcprmd repository.

The following snippet:

import mdtraj as md

t = md.load('../Example_MD/gpcrmd_97/10932_trj_97.xtc', top='../Example_MD/gpcrmd_97/10936_dyn_97.pdb', stride=50)
topology = t.topology

topology.select('resname 1Q5')

Returns an empty array.

Manually renaming the residue to something else resolves the issue.

Not a big deal, but may cause some confusion. Cheers!

[RobertArbon]

you need to use the regex operator for this:

topology.select("resname =~ '^1Q5'")

note - the single quote marks around the expression.

[sukritsingh]

Thanks for responding @RobertArbon ! Yes, select allows for regex operators for residues starting with numbers since that's a fairly uncommon use case (never occurring with proteins, and usually only specific ligands)....Did this work? I can close this issue if so!