On Wed, Jun 1, 2011 at 15:38, Derek Gaston <derek.gaston@inl.gov> wrote:
Has anyone done any MMS verification on cubic hermite convergence rates?  I thought they were supposed to be O(h^4).... but we're only seeing O(h^2) on a fairly simple 2D poisson problem with an assumed solution of u=sin(8*pi*x).

Are you using sufficient quadrature for the Hermite basis?