Run using g++ IntegratorMfemTest.cpp -I -L -l mfem in order to run, use -m to specify the mesh file, -o to specify order, -s to specify size, -n to specify number of elements in each direction, and -t to specify type of element with 1 for tetrahedron and 0 for triangle. mfem version: https://github.com/mfem/mfem/tree/2caa75e35a54df93d19f23655170254556dfc081 For the build: mkdir ; cd cmake make -j 4