Solv_GCP_NS.cpp

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#include <Solv_GCP_NS.h>
#include <Matrice_Bloc_Sym.h>
#include <TRUSTTab_parts.h>
#include <Motcle.h>
#include <Param.h>
#include <Perf_counters.h>
 
Implemente_instanciable(Solv_GCP_NS, "Solv_GCP_NS", solv_iteratif);
// XD gcp_ns solv_gcp gcp_ns INHERITS_BRACE not_set
// XD attr solveur0 solveur_sys_base solveur0 REQ Solver type.
// XD attr solveur1 solveur_sys_base solveur1 REQ Solver type.
 
Sortie& Solv_GCP_NS::printOn(Sortie& s) const
{
  return s;
}
 
Entree& Solv_GCP_NS::readOn(Entree& is)
{
  Param param(que_suis_je());
  set_param(param);
  param.lire_avec_accolades_depuis(is);
  return is;
}
 
void Solv_GCP_NS::set_param(Param& param) const
{
  param.ajouter_non_std("impr", (this));
  param.ajouter("seuil", &seuil_);
  param.ajouter_non_std("solveur0", (this));
  param.ajouter_non_std("solveur1", (this));
  param.ajouter("precond", &le_precond_);
  param.ajouter_non_std("quiet", (this));
}
 
int Solv_GCP_NS::lire_motcle_non_standard(const Motcle& mot, Entree& is)
{
  int retval = 1;
 
  if (mot == "impr")
    fixer_limpr(1);
  else if (mot == "quiet")
    fixer_limpr(-1);
  else if (mot == "solveur0")
    {
      is >> solveur_poisson0;
      solveur_poisson0.nommer("poisson_solver0");
    }
  else if (mot == "solveur1")
    {
      is >> solveur_poisson1;
      solveur_poisson1.nommer("poisson_solver1");
    }
  else
    retval = -1;
 
  return retval;
}
 
static inline void corriger(DoubleVect& X, double alpha, double beta, const DoubleVect& X1, const DoubleVect& X0, int prems, int n)
{
  int sz = prems + n;
  int i = 0;
  for (; i < prems; i++)
    X(i) += beta * X0(i);
  for (; i < sz; i++)
    X(i) += alpha * X1(i - prems);
}
 
static inline void injecter(const DoubleVect& X, DoubleVect& tmp, int prems, int n)
{
  int sz = prems + n;
  for (int i = prems; i < sz; i++)
    tmp(i) = X(i - prems);
}
static inline void extraire(DoubleVect& X, const DoubleVect& tmp, int prems, int n)
{
  int sz = prems + n;
  for (int i = prems; i < sz; i++)
    X(i - prems) = tmp(i);
}
 
inline void erreur()
{
  Cerr << "The dedicated solver GCP_NS can be used only for blocks symetric matrixes" << finl;
  Cerr << "containing 2*2 blocks for VEF discretization P0+P1." << finl;
  Process::exit();
}
 
int Solv_GCP_NS::resoudre_systeme(const Matrice_Base& matrice, const DoubleVect& secmem, DoubleVect& solution, int niter_max)
{
  // A00 X0 + A01 X1 = F0
  // A10 X0 + A11 X1 = F1
  // X1 = A11^(-1) (F1 - A10 X0)
  // X0 = (A00 -A01 A11^(-1) A10) (F0 - A01 A11^(-1) F1)
  //
  // Conjugate gradient on this system preconditioned by A00
  //
  //Cerr << "resoudre_systeme : secmem" << secmem << finl;
 
  //int n = secmem.size();
  assert(solution.size_totale() == secmem.size_totale());
  const int n = secmem.size_totale();
 
  const Matrice_Bloc_Sym& matbloc = ref_cast(Matrice_Bloc_Sym, matrice);
  if (matbloc.nb_bloc_lignes() != 2 || matbloc.nb_bloc_colonnes() != 2)
    erreur();
 
  const Matrice_Base& A00 = matbloc.get_bloc(0, 0);
  const Matrice_Base& A01 = matbloc.get_bloc(0, 1);
  const Matrice_Base& A11 = matbloc.get_bloc(1, 1);
  int n0 = A00.nb_lignes();
  int n1 = A11.nb_lignes();
  const trustIdType nmax_min = 100, nmaxmax=10000000;
  trustIdType nmax0 = std::max(Process::mp_sum(n), nmax_min);
  int nmax = static_cast<int>(std::min(nmax0, nmaxmax));
  int niter = 0;
  double dold, dnew, alfa;
 
  solution = 0.0;
  // Create distributed arrays X1 and F1 on the vertices
  ConstDoubleTab_parts mo_solution(solution);
  DoubleVect X1 = mo_solution[1];
  // DoubleVect X1;
  // champ.domaine().creer_tableau_sommets(X1);
  DoubleVect F1(X1);
  if (X1.size_totale() != n1)
    erreur();
 
  //DoubleVect resu(solution);
 
  // Create distributed arrays X0 and F0 on the elements
  //DoubleVect X0;
  //champ.domaine().creer_tableau_elements(X0);
  //  ConstDoubleTab_parts mo_solution(solution);
  DoubleVect X0 = mo_solution[0];
  DoubleVect F0(X0);
  if (X0.size_totale() != n0)
    erreur();
 
  //F0 :
  extraire(F0, secmem, 0, n0);
  DoubleVect residu(F0);
  //F1 :
  extraire(F1, secmem, n0, n1);
  // X1 = A11^(-1) F1
  solveur_poisson1.resoudre_systeme(A11, F1, X1);
  injecter(X1, solution, n0, n1);
  // F0=A01 X1
  A01.multvect(X1, F0);
  // residu=-F0+A01 X1
  residu -= F0;
  residu *= -1;
  DoubleVect g(F0);
  double norme = mp_norme_vect(residu);
  if (le_precond_)
    le_precond_->preconditionner(A00, residu, g);
  else
    solveur_poisson0.resoudre_systeme(A00, residu, g);
 
  DoubleVect p(g);
  p *= -1.;
 
  dold = mp_prodscal(residu, g);
  dnew = dold;
  if (limpr() > -1)
    Cout << "GCP NS residue = " << norme << " " << finl;
  double s = 0;
  while ((norme > seuil_) && (niter++ < nmax))
    {
      // F1=A10 p
      p.echange_espace_virtuel();
      A01.multvectT(p, F1);
      // X1=-A11^(-1) A10p
      if ((limpr() == 1) && (je_suis_maitre()))
        Cout << "Solveur1: ";
      solveur_poisson1.resoudre_systeme(A11, F1, X1);
      X1 *= -1.;
      //F0=(A00  -A01 A11^(-1) A10) p
      X1.echange_espace_virtuel();
      A01.multvect(X1, F0);
      A00.ajouter_multvect(p, F0);
      s = mp_prodscal(F0, p);
      alfa = dold / (s);
      corriger(solution, alfa, alfa, X1, p, n0, n1);
      residu.ajoute(alfa, F0);
      norme = mp_norme_vect(residu);
      if (norme > seuil_ && dnew > 0)
        {
          if ((limpr() == 1) && (je_suis_maitre()))
            Cout << "Solveur0: ";
          if (le_precond_)
            le_precond_->preconditionner(A00, residu, g);
          else
            solveur_poisson0.resoudre_systeme(A00, residu, g);
          dnew = mp_prodscal(residu, g);
          p *= (dnew / dold);
          p -= g;
          dold = dnew;
          if (dnew < 0)
            {
              Cerr << "Error : dnew<0 in GCP NS solver." << finl;
              Cerr << "Try to reduce the threshold value of solveur0" << finl;
              Cerr << "to a value inferior to those of the GCP NS solver." << finl;
              exit();
            }
        }
      if ((limpr() == 1) && (je_suis_maitre()))
        {
          Cout << "GCP NS residue = " << norme << " " << finl;
          if ((niter % 15) == 0)
            Cout << finl;
        }
    }
  if (norme > seuil_)
    {
      Cerr << "No convergence after : " << niter << " iterations\n";
      Cerr << " Residue : " << norme << "\n";
    }
  solution.echange_espace_virtuel();
  return (niter);
}
 
int Solv_GCP_NS::resoudre_systeme(const Matrice_Base& la_matrice, const DoubleVect& secmem, DoubleVect& solution)
{
  statistics().end_count(STD_COUNTERS::system_solver,-1,0);
  int res = resoudre_systeme(la_matrice, secmem, solution, 1000000);
  statistics().begin_count(STD_COUNTERS::system_solver,statistics().get_last_opened_counter_level()+1);
  return res;
}