Rheolef  7.2
an efficient C++ finite element environment
cahouet-chabart.h

The Cahouet-Chabart preconditioner for the Navier-Stokes equations

#include "neumann-laplace-assembly.h"
cahouet_chabart (const space& Qh, Float lambda_1)
: fact_m(), fact_c(), lambda(lambda_1) {
form m (Qh, Qh, "mass");
fact_m = ldlt(m.uu);
trial p (Qh); test q (Qh);
form_diag dm (Qh, "mass");
field mh (dm);
csr<Float> c = neumann_laplace_assembly (a.uu, mh.u);
fact_c = ldlt(c);
}
vec<Float> solve (const vec<Float>& Mp) const {
vec<Float> q1 = fact_m.solve(Mp);
vec<Float> Mp_e (Mp.size()+1);
for (size_t i = 0; i < Mp.size(); i++) Mp_e.at(i) = Mp.at(i);
Mp_e.at(Mp.size()) = 0;
vec<Float> q2_e = fact_c.solve(Mp_e);
vec<Float> q2 (Mp.size());
for (size_t i = 0; i < q2.size(); i++) q2.at(i) = q2_e.at(i);
vec<Float> q = q1 + lambda*q2;
return q;
}
ssk<Float> fact_m;
ssk<Float> fact_c;
};
see the Float page for the full documentation
see the field page for the full documentation
see the form page for the full documentation
see the space page for the full documentation
see the test page for the full documentation
see the test page for the full documentation
rheolef::details::is_vec dot
std::enable_if< details::has_field_rdof_interface< Expr >::value,details::field_expr_v2_nonlinear_terminal_field< typename Expr::scalar_type,typename Expr::memory_type,details::differentiate_option::gradient >>::type grad(const Expr &expr)
grad(uh): see the expression page for the full documentation
std::enable_if< details::is_field_expr_v2_nonlinear_arg< Expr >::value &&! is_undeterminated< Result >::value, Result >::type integrate(const geo_basic< T, M > &omega, const Expr &expr, const integrate_option &iopt, Result dummy=Result())
see the integrate page for the full documentation
Definition: integrate.h:211
ssk< Float > fact_m
vec< Float > solve(const vec< Float > &Mp) const
cahouet_chabart(const space &Qh, Float lambda_1)
ssk< Float > fact_c
Definition: sphere.icc:25