The issue of constraints on hanging nodes

[PEI0214]

Hello, I would like to learn about how the constraints on 'hanging nodes' are handled in mesh adaptation. Where can I find relevant materials on this?

[jwpeterson]

It is discussed somewhat in the old 2006 libmesh paper, if you have access to that. Some of the information there may be a bit out of date, so your best bet is to look at the code itself, or ask (more specific) questions. Each of the FE classes implements a compute_constraints() API, so it might be instructive to look at one of those, e.g. lagrange_compute_constraints() in src/fe/fe_lagrange.C.