Rheolef  7.2
an efficient C++ finite element environment
burgers_diffusion_error.cc
Go to the documentation of this file.
1
25#include "rheolef.h"
26using namespace rheolef;
27using namespace std;
29int main(int argc, char**argv) {
30 environment rheolef (argc, argv);
31 Float err_expected = (argc > 1) ? atof(argv[1]) : 1;
33 din >> catchmark("epsilon") >> epsilon;
34 branch even("t","u");
35 Float t=0; field uh;
36 Float err_linf_l2 = 0,
37 err_l2_l2 = 0,
38 err_linf_linf = 0,
39 meas_omega = 0;
40 size_t n = 0;
41 bool have_meas_omega = false;
42 dout << "# t err_l2(t) err_linf(t)" << endl;
43 while (din >> even(t,uh)) {
44 const geo& omega = uh.get_geo();
45 if (!have_meas_omega) {
46 meas_omega = integrate(omega);
47 have_meas_omega = true;
48 }
50 iopt.set_order (2*uh.get_space().degree()+1);
51 field pi_h_u = lazy_interpolate (uh.get_space(), u_exact(epsilon,t));
52 Float err_linf = field(uh - pi_h_u).max_abs();
53 Float err_l2 = sqrt(integrate (omega, sqr(uh - u_exact(epsilon,t)), iopt)/meas_omega);
54 err_linf_linf = max(err_linf_linf, err_linf);
55 err_linf_l2 = max(err_linf_l2, err_l2);
56 err_l2_l2 += sqr(err_l2);
57 dout << t << " " << err_l2 << " " << err_linf << endl;
58 ++n;
59 }
60 err_l2_l2 = sqrt(err_l2_l2/n);
61 dout << "# err_l2_l2 = " << err_l2_l2 << endl
62 << "# err_linf_l2 = " << err_linf_l2 << endl
63 << "# err_linf_linf = " << err_linf_linf << endl;
64 return (err_linf_l2 <= err_expected) ? 0 : 1;
65}
int main(int argc, char **argv)
The diffusive Burgers equation – its exact solution.
see the Float page for the full documentation
see the branch page for the full documentation
see the field page for the full documentation
see the geo page for the full documentation
see the catchmark page for the full documentation
Definition: catchmark.h:67
see the environment page for the full documentation
Definition: environment.h:121
see the integrate_option page for the full documentation
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
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
Float epsilon