Mathematics

We introduce quasi-interpolation operators for scalar- and vector-valued finite element spaces with some continuity across mesh interfaces. These operators are stable in L1, are projections, and deliver optimal local approximation estimates in Sobolev spaces. The theory is illustrated on H1-, H(curl)- and H(div)-conforming finite element spaces. This is joint work with J.-L. Guermond. Link: http://cermics.enpc.fr/~ern/home.html