Rheolef  7.2
an efficient C++ finite element environment
cosinusprod_error.cc

The cosinus product function – error analysis for the Poisson problem.

The cosinus product function – error analysis for the Poisson problem

#include "rheolef.h"
using namespace rheolef;
using namespace std;
#include "cosinusprod.h"
int main(int argc, char**argv) {
environment rheolef(argc, argv);
Float err_u_linf_expected = (argc > 1) ? atof(argv[1]) : 1e+38;
field uh; din >> uh;
geo omega = uh.get_geo();
space Xh = uh.get_space();
size_t k = Xh.degree();
size_t d = Xh.get_geo().dimension();
iopt.set_order(min(3*(k+1)+4,size_t(17)));
Float err_u_l2 = sqrt(integrate (omega, sqr(uh-u_exact(d)), iopt));
string opts = Xh.get_basis().option().stamp();
space Xh1 (omega, "P"+to_string(k+1)+"d"+opts);
Float err_u_linf = euh.max_abs();
Float err_u_h1 = sqrt(integrate (omega, norm2(grad_h(euh)), iopt));
dout << "err_u_l2 " << err_u_l2 << endl
<< "err_u_linf " << err_u_linf << endl
<< "err_u_h1 " << err_u_h1 << endl;
return (err_u_linf <= err_u_linf_expected) ? 0 : 1;
}
see the Float page for the full documentation
see the field page for the full documentation
see the geo page for the full documentation
see the environment page for the full documentation
Definition: environment.h:121
see the integrate_option page for the full documentation
see the space page for the full documentation
The cosinus product function.
int main(int argc, char **argv)
space_basic< T, M > Xh1
Definition: field_expr.h:232
This file is part of Rheolef.
field_basic< T, M > lazy_interpolate(const space_basic< T, M > &X2h, const field_basic< T, M > &u1h)
see the interpolate page for the full documentation
Definition: field.h:871
T norm2(const vec< T, M > &x)
norm2(x): see the expression page for the full documentation
Definition: vec.h:379
std::enable_if< details::has_field_rdof_interface< Expr >::value, details::field_expr_v2_nonlinear_terminal_field< typenameExpr::scalar_type, typenameExpr::memory_type, details::differentiate_option::gradient > >::type grad_h(const Expr &expr)
grad_h(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
STL namespace.
rheolef - reference manual
g u_exact
Definition: taylor_exact.h:26