Finite Element Assembly Using an Embedded Domain Specific Language

Listing 17

The code for the correction step in Chorin’s method.

) Handle<LSSActionUnsteady> correction_lss = create_component<LSSActionUnsteady>("

     CorrectionLSS");

()

() Handle<ProtoAction> correction_matrix_assembly = correction_lss->create_component<

    ProtoAction>("MatrixAssembly");

() correction_matrix_assembly->set_expression(elements_expression(LagrangeP1P2(),

() group

() (

()  _A(u) = _0,

()  element_quadrature(_A(u[_i], u[_i]) += transpose(N(u))*N(u)),

()  correction_lss->system_matrix += _A

() )));

()

() Handle<ProtoAction> correction_rhs_assembly = correction_lss->create_component<ProtoAction>(

     "RHSAssembly");

() correction_rhs_assembly->set_expression(elements_expression(LagrangeP1P2(),

() group

() (

()  _a[u] = _0,

()  element_quadrature(_a[u[_i]] +=

()   transpose(N(u))*(u[_i] − lit(correction_lss->dt()) * gradient(p)[_i])),

()  correction_lss->system_rhs += _a

() )));