MassMatrix_test_4

This example shows how to USE the SUBROUTINE called MassMatrix to create a mass matrix in space domain.

Here, we want to DO the following.

$$\int_{\Omega } N^{I}\rho N^{J}d\Omega$$

rho can be a constant, or a FUNCTION of spatial coordinates, or some nonlinear FUNCTION.

In this example, following mass matrix is formed for ReferenceLine element, QuadraturePoint are GaussLegendre.

$$\int_{\Omega } N^{I} N^{J}d\Omega$$

This TYPE of mass matrix is useful when $rho$ is a constant.