[Getdp] lumping method

[Lin Ji]

Dear Christophe,
   Have you heared of the lumping method that simply replace the mass matrix
by a diagonal matrix when solving the wave equation? It makes solving the
linear system at each time step explicit and therefore much faster. It seems
it is quite popular in the world of mechanical engineering or control theory.
I am not sure about the mathematical justification behind it. I just know it
from a speaker from the mechanical engineering department.
   I am wondering if you can take a look at it and maybe impletment it in
GetDP. I am still quite interested in a faster method solving wave equation
especiall in 3D case. If you need any reference, I can ask the speaker for
you.
   We are still writing up the paper that use GetDP to simulate the data. I
will let you know when it is published. Thanks.

Lin Ji

-- 
Dept. of Math., RPI
518-276,8377 (work)