DG_discretisation.cpp

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#include <DG_discretisation.h>
#include <Domaine_DG.h>
#include <Champ_Fonc_Tabule.h>
#include <Milieu_base.h>
#include <Equation_base.h>
#include <Champ_Uniforme.h>
#include <Champ_Inc_base.h>
#include <Schema_Temps_base.h>
#include <Motcle.h>
#include <Domaine_Cl_DG.h>
#include <Option_DG.h>
#include <Quadrature_base.h>
#include <Quadrature_Ord1_Polygone.h>
#include <Quadrature_Ord3_Polygone.h>
#include <Quadrature_Ord5_Polygone.h>
 
Implemente_instanciable(DG_discretisation, "DG", Discret_Thyd);
// XD DG discretisation_base DG INHERITS_BRACE DG discretization
 
 
Entree& DG_discretisation::readOn(Entree& s)
{
  return Discret_Thyd::readOn(s);
}
 
Sortie& DG_discretisation::printOn(Sortie& s) const { return s; }
 
/*! @brief Discretisation of a field for DG formulation
 *
 * TODO, refactor this after stokes. And decide if we want to put this on Option_DG or not
 *
 * The directive is a Motcle such as "vitesse", "pression",
 *  "temperature", "champ_elem" (creates a field of type P0), ...
 *  This method determines the type of field to create based on the element type
 *  and the discretisation directive. It then determines the number of DOFs
 *  and sets all the field parameters (type, nb_compo, nb_ddl, nb_pas_dt,
 *  name(s), unit(s) and field nature) and associates the Domaine_dis to the field.
 *  See the code for the mapping between directives and the created field type.
 *
 */
void DG_discretisation::discretiser_champ(const Motcle& directive, const Domaine_dis_base& dom_dis, Nature_du_champ nature, const Noms& noms, const Noms& unites, int nb_comp, int nb_pas_dt,
                                          double temps, OWN_PTR(Champ_Inc_base)& champ, const Nom& sous_type) const
{
  Motcles motcles(7);
  motcles[0] = "vitesse";     // Standard choice for velocity
  motcles[1] = "pression";    // Standard choice for pressure
  motcles[2] = "temperature"; // Standard choice for temperature
  motcles[3] = "divergence_vitesse"; // Field type obtained by computing div v
  motcles[4] = "gradient_pression";  // Field type obtained by computing grad P
  motcles[5] = "champ_elem";    // Create a field at elements (type P0)
  motcles[6] = "champ_sommets"; // Create a field at vertices (type P1)
  // The velocity field type depends on the element type:
//  Nom type_champ_vitesse("Champ_Face_DG");
  Nom type_elem("Champ_Elem_DG");
  Nom type;
  int nb_basis_func = 0; // Default value for the number of components
  int rang = motcles.search(directive);
  const int order_DG = Option_DG::Get_order_for(noms[0]);
  switch(rang)
    {
    case 0:
    case 1:
    case 2:
    case 3:
    case 4:
    case 5:
      type = type_elem;
      nb_basis_func = Option_DG::Nb_col_from_order(order_DG);
      break;
    default:
      assert(rang < 0);
      break;
    }
 
  if (directive == DEMANDE_DESCRIPTION)
    Cerr << "DG discretisation : " << motcles;
 
  if (sous_type != NOM_VIDE)
    rang = verifie_sous_type(type, sous_type, directive);
 
  // If the directive was not understood (or if it is a description request),
  // call the parent class:
  if (rang < 0)
    {
      Discret_Thyd::discretiser_champ(directive, dom_dis, nature, noms, unites, nb_comp, nb_pas_dt, temps, champ);
      return;
    }
 
  // Compute the number of degrees of freedom
  int nb_ddl = 0;
  if (type.debute_par(type_elem))
    nb_ddl = dom_dis.nb_elem();
  else
    assert(0);
 
  creer_champ(champ, dom_dis, type, noms[0], unites[0], nb_comp*nb_basis_func, nb_ddl, nb_pas_dt, temps, directive, que_suis_je());
 
  if (nature == multi_scalaire)
    {
      throw;
    }
 
  if (nb_comp == 1)
    switch(order_DG)
      {
      case 0:
        champ->fixer_nature_du_champ(scalaire);
        break;
      case 1:
        champ->fixer_nature_du_champ(basis_function_order_1_scalar);
        break;
      case 2:
        champ->fixer_nature_du_champ(basis_function_order_2_scalar);
        break;
      default:
        assert(0);
      }
  else
    switch(order_DG)
      {
      case 0:
        champ->fixer_nature_du_champ(vectoriel);
        break;
      case 1:
        champ->fixer_nature_du_champ(basis_function_order_1_vectorial);
        break;
      case 2:
        champ->fixer_nature_du_champ(basis_function_order_2_vectorial);
        break;
      default:
        assert(0);
      }
 
 
}
 
/*! @brief Same as DG_discretisation::discretiser_champ(.
 *
 * .. , Champ_Inc)
 *
 */
void DG_discretisation::discretiser_champ(const Motcle& directive, const Domaine_dis_base& z, Nature_du_champ nature, const Noms& noms, const Noms& unites, int nb_comp, double temps,
                                          OWN_PTR(Champ_Fonc_base)& champ) const
{
  discretiser_champ_fonc_don(directive, z, nature, noms, unites, nb_comp, temps, champ);
}
 
/*! @brief Same as DG_discretisation::discretiser_champ(.
 *
 * .. , Champ_Inc)
 *
 */
void DG_discretisation::discretiser_champ(const Motcle& directive, const Domaine_dis_base& z, Nature_du_champ nature, const Noms& noms, const Noms& unites, int nb_comp, double temps,
                                          OWN_PTR(Champ_Don_base)& champ) const
{
  discretiser_champ_fonc_don(directive, z, nature, noms, unites, nb_comp, temps, champ);
}
 
/*! @brief Same as DG_discretisation::discretiser_champ(.
 *
 * .. , Champ_Inc) Common processing for champ_fonc and champ_don.
 *  This method is private (passing an Objet_U is not clean from the outside).
 *
 */
void DG_discretisation::discretiser_champ_fonc_don(const Motcle& directive, const Domaine_dis_base& z, Nature_du_champ nature, const Noms& noms, const Noms& unites, int nb_comp, double temps,
                                                   Objet_U& champ) const
{
  // Two pointers for easy access to champ_don or champ_fonc, depending on the type of the champ object.
  OWN_PTR(Champ_Fonc_base) * champ_fonc = dynamic_cast<OWN_PTR(Champ_Fonc_base)*>(&champ);
  OWN_PTR(Champ_Don_base) * champ_don = dynamic_cast<OWN_PTR(Champ_Don_base)*>(&champ);
 
  const Domaine_DG& domaine_DG = ref_cast(Domaine_DG, z);
 
 
  Motcles motcles(8);
  motcles[0] = "pression";    // Standard choice for pressure
  motcles[1] = "temperature"; // Standard choice for temperature
  motcles[2] = "champ_fonc_quad_dg"; // With value on quadrature points
  motcles[5] = "champ_elem_dg"; // With value on quadrature points
  motcles[3] = "champ_elem";  // Create a field at elements (type P0)
  motcles[6] = "champ_sommets";  // Create a field at vertices (type P1)
  motcles[4] = "vitesse";     // Standard choice for velocity
  motcles[7] = "champ_face";     // Standard choice for velocity
 
  Nom type;
  int nb_points = 0; // Default value for the number of components
  int rang = motcles.search(directive);
  const Quadrature_base& quad = domaine_DG.get_quadrature(5); // TODO: Make this depend from the order of discretization ...
  int nb_pts_integ_max = quad.nb_pts_integ_max();
 
//  const int order_DG = Option_DG::Get_order_for(directive);
  switch(rang)
    {
    case 0:
    case 1:
    case 2:
    case 4:
    case 5:
    case 7:
      type = "Champ_Fonc_Quad_DG";
      nb_points = nb_pts_integ_max; //Option_DG::Nb_col_from_order(order_DG);;
      break;
    case 3:
      type = "Champ_Fonc_Elem_DG";
      nb_points = 1;
      break;
    case 6:
      type = "Champ_Fonc_Som_DG";
      nb_points = 1;
      break;
    default:
      assert(rang < 0);
      break;
    }
 
  if (directive == DEMANDE_DESCRIPTION)
    Cerr << "DG discretisation : " << motcles;
 
  // If the directive was not understood (or if it is a description request),
  // call the parent class:
  if (rang < 0)
    {
      if (champ_fonc)
        Discret_Thyd::discretiser_champ(directive, z, nature, noms, unites, nb_comp, temps, *champ_fonc);
      else
        Discret_Thyd::discretiser_champ(directive, z, nature, noms, unites, nb_comp, temps, *champ_don);
      return;
    }
 
  // Compute the number of degrees of freedom
  int nb_ddl = 0;
  if (type == "Champ_Fonc_Elem_DG" || type == "Champ_Fonc_Quad_DG")
    nb_ddl = z.nb_elem();
  else if (type == "Champ_Fonc_Som_DG")
    nb_ddl = domaine_DG.nb_som();
  else
    assert(0);
 
  bool vector = (nature==vectoriel or nature==quadrature_vectoriel or nature == basis_function_order_1_vectorial or nature == basis_function_order_2_vectorial );
  if (vector) nb_comp = dimension;
  else nb_comp = 1;
  if (champ_fonc)
    {
      creer_champ(*champ_fonc, z, type, noms[0], unites[0], nb_comp*nb_points, nb_ddl, temps, directive, que_suis_je());
      if (nb_comp == 1)
        {
          (nb_points == 1) ? champ_fonc->valeur().fixer_nature_du_champ(scalaire)
          : champ_fonc->valeur().fixer_nature_du_champ(quadrature_scalaire);
        }
      else if (nb_comp == dimension)
        {
          (nb_points == 1) ? champ_fonc->valeur().fixer_nature_du_champ(vectoriel)
          : champ_fonc->valeur().fixer_nature_du_champ(quadrature_vectoriel);
        }
      else
        {
          Cerr << "multi_scalaire not implemented for now" << finl;
          exit();
        }
    }
  else
    {
      creer_champ(*champ_don, z, type, noms[0], unites[0], nb_comp*nb_points, nb_ddl, temps, directive, que_suis_je());
      if (nb_comp == 1)
        {
          (nb_points == 1) ? champ_don->valeur().fixer_nature_du_champ(scalaire)
          : champ_don->valeur().fixer_nature_du_champ(quadrature_scalaire);
        }
      else if (nb_comp == dimension)
        {
          (nb_points == 1) ? champ_don->valeur().fixer_nature_du_champ(vectoriel)
          : champ_don->valeur().fixer_nature_du_champ(quadrature_vectoriel);
        }
      else
        {
          Cerr << "multi_scalaire not implemented for now" << finl;
          exit();
        }
    }
 
 
 
  if ((nature == multi_scalaire) && (champ_fonc))
    {
      throw;
    }
  else if ((nature == multi_scalaire) && (champ_don))
    {
      Cerr << "There is no field of type Champ_Don with a multi_scalaire nature." << finl;
      exit();
    }
}
 
void DG_discretisation::distance_paroi(const Schema_Temps_base& sch, Domaine_dis_base& z, OWN_PTR(Champ_Fonc_base)& ch) const
{
  throw;
}
 
 
void DG_discretisation::grad_u(const Domaine_dis_base& z, const Domaine_Cl_dis_base& zcl, const Champ_Inc_base& ch_vitesse, OWN_PTR(Champ_Fonc_base)& ch) const
{
  throw;
}
 
 
void DG_discretisation::modifier_champ_tabule(const Domaine_dis_base& domaine_poly, Champ_Fonc_Tabule& lambda_tab, const VECT(OBS_PTR(Champ_base)) &champs_param) const
{
  throw;
}
 
/*! @brief Old copy paste, give the name to fields. Name used to allocate size of matrixes in discretiser
 *
 */
Nom DG_discretisation::get_name_of_type_for(const Nom& class_operateur, const Nom& type_operateur, const Equation_base& eqn, const OBS_PTR(Champ_base) &champ_sup) const
{
  Nom type;
  if (class_operateur == "Source")
    {
      type = type_operateur;
      Nom champ = (eqn.inconnue().que_suis_je());
      champ.suffix("Champ");
      type += champ;
      //type+="_DG";
      return type;
 
    }
  else if (class_operateur == "Solveur_Masse")
    {
      Nom type_ch = eqn.inconnue().que_suis_je();
      if (type_ch.debute_par("Champ_Elem"))
        type_ch = "_Elem";
 
      if (type_ch.debute_par("Champ_Face"))
        type_ch = "_Face";
 
      type = "Masse_DG";
      type += type_ch;
    }
  else if (class_operateur == "Operateur_Grad")
    {
      type = "Op_Grad_DG";
    }
  else if (class_operateur == "Operateur_Div")
    {
      type = "Op_Div_DG";
    }
 
  else if (class_operateur == "Operateur_Diff")
    {
      Nom type_ch = eqn.inconnue().que_suis_je();
      if (type_ch.debute_par("Champ_Elem"))
        type_ch = "_Elem";
 
      if (type_ch.debute_par("Champ_Face"))
        type_ch = "_Face";
 
      type = "Op_Diff";
      if (type_operateur != "")
        {
          type += "_";
          type += type_operateur;
        }
      type += "_DG";
      type += type_ch;
    }
  else if (class_operateur == "Operateur_Conv")
    {
      type = "Op_Conv_";
      type += type_operateur;
      Nom tiret = "_";
      type += tiret;
      type += que_suis_je();
      Nom type_ch = eqn.inconnue().que_suis_je();
      if (type_ch.debute_par("Champ_Elem"))
        type += "_Elem";
      if (type_ch.debute_par("Champ_Face"))
        type += "_Face";
      type += "_DG";
    }
 
  else
    return Discret_Thyd::get_name_of_type_for(class_operateur, type_operateur, eqn);
 
  return type;
}
 
void DG_discretisation::distance_paroi_globale(const Schema_Temps_base& sch, Domaine_dis_base& z, OWN_PTR(Champ_Fonc_base)& ch) const
{
  Cerr << "Global wall distance discretisation" << finl;
  Noms noms(1), unites(1);
  noms[0] = Nom("distance_paroi_globale");
  unites[0] = Nom("m");
  discretiser_champ(Motcle("champ_elem"), z, scalaire, noms, unites, 1, 0, ch);
}