Rheolef  7.1
an efficient C++ finite element environment
stokes_taylor_error_dg.cc
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1 #include "rheolef.h"
26 using namespace rheolef;
27 using namespace std;
28 #include "taylor_exact.h"
29 int main(int argc, char**argv) {
30  environment rheolef(argc, argv);
31  Float err_linf_expected = (argc > 1) ? atof(argv[1]) : 1e+38;
32  bool dump = (argc > 2);
33  field uh;
34  din >> uh;
35  space Xh = uh.get_space();
36  geo omega = Xh.get_geo();
37  space Qh (omega, Xh.get_approx());
38  field ph(Qh);
39  din >> ph;
40  size_t k = Xh.degree();
41  size_t d = omega.dimension();
42  integrate_option iopt;
44  iopt.set_order(2*k+1);
45  Float meas_omega = integrate (omega);
46  Float moy_ph = integrate (omega, ph, iopt);
47  ph = ph - moy_ph/meas_omega; // ph with zero average value
48  string high_approx = "P"+itos(k+1)+"d";
49  space Xh1 (omega, high_approx, "vector"),
50  Qh1 (omega, high_approx);
51  field euh = interpolate (Xh1, uh-u_exact());
52  field eph = interpolate (Qh1, ph-p_exact());
53  Float err_u_l2 = sqrt(integrate (omega, norm2(uh-u_exact()), iopt));
54  Float err_u_linf = euh.max_abs();
55  Float err_u_h1 = sqrt(integrate (omega, norm2(grad_h(euh)), iopt)
56  + integrate (omega.sides(), (1/h_local())*norm2(jump(euh)), iopt));
57  Float err_p_l2 = sqrt(integrate (omega, sqr(ph-p_exact()), iopt));
58  Float err_p_linf = eph.max_abs();
59  derr << "err_u_l2 = " << err_u_l2 << endl
60  << "err_u_linf = " << err_u_linf << endl
61  << "err_u_h1 = " << err_u_h1 << endl
62  << "err_p_l2 = " << err_p_l2 << endl
63  << "err_p_linf = " << err_p_linf << endl;
64  if (dump) {
65  dout << catchmark("uh") << uh
66  << catchmark("u") << interpolate (Xh, u_exact())
67  << catchmark("eu") << euh
68  << catchmark("ph") << ph
69  << catchmark("p") << interpolate (Qh, p_exact())
70  << catchmark("ep") << eph;
71  }
72  return (max(err_u_linf,err_p_linf) <= err_linf_expected) ? 0 : 1;
73 }
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 catchmark page for the full documentation
Definition: catchmark.h:67
see the environment page for the full documentation
Definition: environment.h:115
see the integrate_option page for the full documentation
void set_family(family_type type)
idiststream din
see the diststream page for the full documentation
Definition: diststream.h:427
odiststream dout(cout)
see the diststream page for the full documentation
Definition: diststream.h:430
odiststream derr(cerr)
see the diststream page for the full documentation
Definition: diststream.h:436
see the space page for the full documentation
verbose clean transpose logscale grid shrink ball stereo iso volume skipvtk deformation fastfieldload lattice reader_on_stdin color format format format format format format format format format format format format format format format format format format dump
This file is part of Rheolef.
details::field_expr_v2_nonlinear_terminal_function< details::h_local_pseudo_function< Float > > h_local()
h_local: see the expression page for the full documentation
std::enable_if< details::is_field_convertible< Expr >::value,details::field_expr_v2_nonlinear_terminal_field< typename Expr::scalar_type,typename Expr::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:202
field_basic< T, M > interpolate(const space_basic< T, M > &V2h, const field_basic< T, M > &u1h)
see the interpolate page for the full documentation
Definition: interpolate.cc:233
T norm2(const vec< T, M > &x)
norm2(x): see the expression page for the full documentation
Definition: vec.h:379
std::string itos(std::string::size_type i)
itos: see the rheostream page for the full documentation
rheolef - reference manual
int main(int argc, char **argv)
The Taylor benchmark – the exact solution of the Stokes problem.
g u_exact
Definition: taylor_exact.h:26