In most (maybe all) force fields the terminal residues of nucleic acids have partial charges, but the 5' and 3' termini add to -1. (eg in AMBER for RNA that charges are -0.3081, -0.6919). In main.py line 689 there is a check that each residue has an integer charge which NA should all fail. One fix I implemented is to change this check to checking that the sum of all residue charges is an integer, but not sure if that is desired behavior / if there was a reason to check each residue individually.
In most (maybe all) force fields the terminal residues of nucleic acids have partial charges, but the 5' and 3' termini add to -1. (eg in AMBER for RNA that charges are -0.3081, -0.6919). In main.py line 689 there is a check that each residue has an integer charge which NA should all fail. One fix I implemented is to change this check to checking that the sum of all residue charges is an integer, but not sure if that is desired behavior / if there was a reason to check each residue individually.