GROMACS version: 2022-3
GROMACS modification: Yes
A low priority question since I have a workaround but:
I too am attempting to measure the angle between rings. I’d like to use the -n option and select index groups interactively instead of using the selection syntax in the -group1/2 flags.
I ran into a slight hiccup: I cannot figure out the key sequence or command to inform the gangle that I have finished entering index groups for group1 and now want to move on to group2.