# Tag Info

In 2D your volume part consists of a double integral, whereas the surface part is a standard line integral. Generally this is described with tensorial notations. If you consider the Cartesian case, the volume part results in a mass matrix similar to $M_{\Omega}\equiv \mathbf{M}_{\text{1}} \otimes \mathbf{M}_{\text{1}}$, whereas the surface part results in a ...