Partitionneur_Fichier_MED.cpp

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#include <Partitionneur_Fichier_MED.h>
#include <EFichier.h>
#include <Domaine.h>
#include <medcoupling++.h>
#include <Param.h>
#ifdef MEDCOUPLING_
#include <MEDLoader.hxx>
#include <MEDCouplingField.hxx>
#include <MEDCouplingFieldInt32.hxx>
#pragma GCC diagnostic ignored "-Wreorder"
#include <MEDFileField.hxx>
#include <communications.h>
#include <Champ_Fonc_MED.h>
#include <EChaine.h>
 
#endif
 
// XD Partitionneur_Fichier_MED partitionneur_deriv fichier_med INHERITS_BRACE Partitioning a domain using a MED file
// XD_CONT containing an integer field providing for each element the processor number on which the element should be
// XD_CONT located.
Implemente_instanciable_sans_constructeur(Partitionneur_Fichier_MED,"Partitionneur_Fichier_MED",Partitionneur_base);
 
Partitionneur_Fichier_MED::Partitionneur_Fichier_MED()
{
}
 
Sortie& Partitionneur_Fichier_MED::printOn(Sortie& os) const
{
  Cerr << "Partitionneur_MED::printOn invalid\n" << finl;
  exit();
  return os;
}
 
/*! @brief Reads the partitioner parameters from disk.
 *
 * Expected format:
 *     { file FILENAME field FIELDNAME }
 *   FILENAME is the name of a MED file; the FIELDNAME field contains an ArrayOfInt with the processor number.
 *
 */
void Partitionneur_Fichier_MED::set_param(Param& param) const
{
  param.ajouter("file",&filename_,Param::REQUIRED); // XD_ADD_P chaine
  // XD_CONT file name of the MED file to load
  param.ajouter("field",&fieldname_,Param::OPTIONAL); // XD_ADD_P chaine
  // XD_CONT field name of the integer (or double) field to load
}
 
void Partitionneur_Fichier_MED::associer_domaine(const Domaine& domaine)
{
  ref_domaine_ = domaine;
}
 
void Partitionneur_Fichier_MED::initialiser(const char *filename)
{
  filename_ = filename;
}
 
/*! @brief Reads the content of "filename_" and stores the result in elem_part.
 *
 */
void Partitionneur_Fichier_MED::construire_partition(IntVect& elem_part, int& nb_parts_tot) const
{
  if (!ref_domaine_)
    {
      Cerr << "Error in Partitionneur_Fichier_MED::construire_partition\n";
      Cerr << " The domain has not been associated" << finl;
      exit();
    }
  if (filename_ == "")
    {
      Cerr << "Error in Partitionneur_Fichier_MED::construire_partition\n";
      Cerr << " The file name has not been initialized" << finl;
      exit();
    }
  if (fieldname_ == "")
    {
      Cerr << "Error in Partitionneur_Fichier_MED::construire_partition\n";
      Cerr << " The field name has not been initialized" << finl;
      exit();
    }
 
  Cerr << "Reading of splitting file : " << filename_ << finl;
 
#ifdef MEDCOUPLING_
  using namespace MEDCoupling;
 
  MCAuto<MEDCouplingField> ffield = MEDCoupling::ReadField(filename_.getString(), fieldname_.getString());
  MEDCouplingFieldInt32 * field = dynamic_cast<MEDCouplingFieldInt32 *>((MEDCouplingField *)ffield);
  if(field)
    {
      // Reading an exact partition of the domain given by an integer field
      DataArrayInt32 *da = field->getArray();
      const int *field_values = da->begin();
 
      const mcIdType sz0 = field->getNumberOfTuplesExpected();
      assert(sz0 < std::numeric_limits<int>::max());
      const int sz = static_cast<int>(sz0);
      elem_part.resize(sz);
      std::copy(field_values, field_values + sz, elem_part.addr());
      // Sanity check
      const int nelem = ref_domaine_->nb_elem();
      if (nelem != sz)
        {
          Cerr << "Error in Partitionneur_Fichier_MED::construire_partition" << finl;
          Cerr << " The file contains an array of " << sz << " values." << finl;
          Cerr << " The area contains " << nelem << " elements" << finl;
          exit();
        }
      // Checking that the full range is covered
      MCAuto<DataArrayInt32> das = da->buildUniqueNotSorted();
      MCAuto<DataArrayInt32> iot(DataArrayInt32::New());
      mcIdType dnu;
      const mcIdType max_v = das->getMaxValue(dnu);
      iot->alloc(max_v + 1, 1);
      iot->iota();
      if (!iot->isEqualWithoutConsideringStr(*das))
        {
          Cerr << "Error in Partitionneur_Fichier_MED::construire_partition" << finl;
          Cerr << " The file contains/lacks integer values which do not cover the range [0; n_elem[." << finl;
          Cerr << " Are some field values missing?" << finl;
          exit();
        }
#else
  Cerr << "Partitionneur_Fichier_MED requires TRUST compiled with MEDCoupling support!" << finl;
  exit();
#endif
    }
  else
    {
      // Reading a partition of a domain that partially covers the domain, given by a double field:
      /*
        Decouper outer_domain {
              partitionneur metis { nb_parts 3 } zones_name outer_domain
              ecrire_med outer_domain.med
              }
        Decouper inner_domain {
              partitionneur fichier_med { file outer_domain_0000.med }
              zones_name inner_domain
        }
      */
      // Read the partition field with Champ_Fonc_MED:
      Nom cli("");
      cli+="{ file ";
      cli+=filename_;
      cli+=" domain ";
      cli+= ffield->getMesh()->getName();
      cli+=" field partition loc elem last_time }";
      EChaine ech(cli);
      Champ_Fonc_MED partition_field_outer_domain;
      ech >> partition_field_outer_domain;
      // Mapping between local domain and the field domain:
      int nb_elem = ref_domaine_->nb_elem();
      DoubleTab xp_elems;
      ref_domaine_->calculer_centres_gravite(xp_elems);
      IntVect elems(nb_elem);
      partition_field_outer_domain.domaine().chercher_elements(xp_elems, elems);
      DoubleTab double_elem_part(nb_elem);
      double_elem_part = -1;
      partition_field_outer_domain.valeur_aux_elems(xp_elems, elems, double_elem_part);
      if (local_min_vect(double_elem_part)<0)
        {
          Cerr << "The domain " << ref_domaine_->le_nom() << " it not fully included into the domain " <<  ffield->getMesh()->getName() << " ! " << finl;
          Cerr << "It is mandatory to use the partition field from " << filename_ << finl;
          Process::exit();
        }
      // Convert double to int to fill elem_part:
      elem_part.resize(nb_elem);
      for (int i=0; i<nb_elem; i++)
        elem_part(i)=(int)double_elem_part(i);
      nb_parts_tot = 1+int(local_max_vect(partition_field_outer_domain.valeurs()));
      return;
    }
}