From: Kirk, Benjamin (JSCEG311) <benjamin.kirk@na...>  20140117 16:28:51

On Jan 17, 2014, at 10:10 AM, subramanya sadasiva <potaman@...> wrote: > Thanks.I wanted to try and keep it simple to alternate between lumped and full mass matrices. I had a doubt about using them with adaptivity. will solving , followed by applying constraints exactly give me the correct results? > Subramanya I'll see if I can find a reference, but I recall reading that since the mass matrix is so nice it can be iteratively solved via Jacobi or GaussSiedel iteration as Mu = f (D + OD)u = f Du = f  ODu Du^{l+1} = f  ODu^l where D is diagonal and OD is the rest… Now, I'd love a patch that basically implements that if you are feeling ambitious… For the lumped case of course OD=0 and everything converges in one iteration. Ben 