int GridCalcElementVecIndices_Triangular_2D(Grid, Mesh, int, VarOrdering, VarOrdering, PetscTruth, PetscTruth, ElementVec);
int GridProjectElementVec_Triangular_2D(Grid, Mesh, int, VarOrdering, VarOrdering, PetscTruth, PetscTruth, ElementVec);
int GridCalcBoundaryElementVecIndices_Triangular_2D(Grid, int, int, int, VarOrdering, VarOrdering, PetscTruth, ElementVec);

int GridCalcElementMatIndices_Triangular_2D(Grid, int, VarOrdering, VarOrdering, VarOrdering, PetscTruth, ElementMat);
int GridCalcBoundaryElementMatIndices_Triangular_2D(Grid, int, int, int, VarOrdering, VarOrdering, VarOrdering, PetscTruth, ElementMat);