Fande Kong <[email protected]> writes: > On Wed, Feb 14, 2018 at 4:35 PM, Smith, Barry F. <[email protected]> wrote: > >> >> What are you doing with the matrix? >> > > We are doing an explicit method. PDEs are discretized using a finite > element method, so there is a mass matrix. The mass matrix will be lumped, > and it becomes diagonal. We want to compute the inverse of the lumped > matrix, and also do a few of matrix-vector multiplications using the > lumped matrix or its inverse. > > The specific implementation won't make this more efficient?
You can use pretty much any representation and you won't notice the time because you still have to apply the RHS operator and that is vastly more expensive.
