Solv_Cholesky.cpp

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#include <Solv_Cholesky.h>
#include <Matrice_Bloc_Sym.h>
#include <Motcle.h>
#include <Sparskit.h>
#include <Lapack.h>
#include <EFichier.h>
#include <Param.h>
 
//Solv_Cholesky::deja_factorise_=0;
 
Implemente_instanciable_sans_constructeur_ni_destructeur(Solv_Cholesky,"Solv_Cholesky",SolveurSys_base);
// XD cholesky solveur_sys_base cholesky INHERITS_BRACE Cholesky direct method.
// XD attr impr rien impr OPT Keyword which may be used to print the resolution time.
// XD attr quiet rien quiet OPT To disable printing of information
 
// printOn and readOn
 
Sortie& Solv_Cholesky::printOn(Sortie& s ) const
{
  return s << que_suis_je() << finl;
}
 
Entree& Solv_Cholesky::readOn(Entree& is )
{
  if ( Process::is_parallel() )
    {
      Cerr << finl;
      Cerr << "Cholesky solver not parallelized in TRUST!!!" << finl;
      Cerr << "Change your solver." << finl;
      Cerr << "Try using Petsc Cholesky solver." << finl;
      exit();
    }
  Param param(que_suis_je());
  set_param(param);
  param.lire_avec_accolades_depuis(is);
  return is;
}
 
void Solv_Cholesky::set_param(Param& param) const
{
  param.ajouter_non_std("impr",(this));
  param.ajouter("save_matrice|save_matrix",&save_matrice_);
  param.ajouter_non_std("quiet",(this));
}
 
int Solv_Cholesky::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 retval = -1;
 
  return retval;
}
 
int Solv_Cholesky::resoudre_systeme(const Matrice_Base& la_matrice,
                                    const DoubleVect& secmem,
                                    DoubleVect& solution)
{
  Cerr << "Warning, Sparskit based Cholesky solver will be deprecated soon. Consider using PETSc Cholesky solver. Contact trust@cea.fr if you can't for some specific reason." << finl;
  if(sub_type(Matrice_Morse_Sym,la_matrice))
    {
      const Matrice_Morse_Sym& matrice = ref_cast(Matrice_Morse_Sym,la_matrice);
      return Cholesky(matrice,secmem,solution);
    }
  else
    {
      if(sub_type(Matrice_Bloc_Sym,la_matrice))
        {
          // Convert a Matrice_Bloc_Sym matrix to Matrice_Morse format
          if (nouvelle_matrice())
            ref_cast(Matrice_Bloc_Sym,la_matrice).BlocSymToMatMorseSym(matrice_de_travail);
          return Cholesky(matrice_de_travail,secmem,solution);
        }
      else if(sub_type(Matrice_Bloc,la_matrice))
        {
          const Matrice_Bloc& matrice = ref_cast(Matrice_Bloc,la_matrice);
          if((matrice.nb_bloc_lignes()>1 && ref_cast(Matrice_Morse,matrice.get_bloc(1,0).valeur()).nb_lignes()>0))
            {
              Cerr<<"Solv_Cholesky : WARNING : Cholesky by blocks cannot be done"<<finl;
              exit();
              return(-1);
            }
          const Matrice_Morse_Sym& MB00 = ref_cast(Matrice_Morse_Sym,matrice.get_bloc(0,0).valeur());
          return Cholesky(MB00,secmem,solution);
        }
      else
        {
          Cerr<<"Solv_Cholesky : Warning : one is not able to carry out preconditionning for linear systems based on Matrice_Morse_Sym or Matrice_Bloc type matrixes"<<finl;
          exit();
          return(-1);
        }
    }
}
 
int Solv_Cholesky::Cholesky(const Matrice_Morse_Sym& matrice,
                            const DoubleVect& secmem,
                            DoubleVect& solution)
{
  auto nzmax = matrice.get_tab1().size_array();
  if (nzmax>std::numeric_limits<int>::max())
    Process::exit("Cholesky can't solve this system.");
 
  if (nouvelle_matrice())
    {
      fixer_nouvelle_matrice(0);
      // Make the matrix positive-definite in sequential mode where Cholesky is the pressure solver
      // In parallel, Cholesky is used as a local preconditioner and the local matrix must not be modified.
      Cerr << "Order of the matrix : " << matrice.ordre() << finl;
      // P1bulle fields have no size_reelle and this does not work in parallel...
      const int sz = secmem.size_totale();
      if(matrice.get_est_definie()==0 && nproc()==1)
        {
          Cerr << "Matrix not defined : " << finl;
          Cerr << "zero value is imposed at point 0" << finl;
          Matrice_Morse_Sym& mat = ref_cast_non_const(Matrice_Morse_Sym,matrice);
          mat(0,0)*=1E+6;
        }
      matrice.renumerote();
      Fact_Cholesky(matrice.matrice_renumerotee(),sz);
    }
 
 
  DoubleVect vecteur(secmem);
  const int n = secmem.size_totale();//ordre;
 
  // permutation of the RHS
  // subroutine dvperm (n, x, perm)
  // SPARSKIT2/FORMATS/unary.f
  F77NAME(DVPERM)(&n, vecteur.addr(), matrice.permutation().addr());
 
  char UPLO = 'U';                          // A is upper triangular
  int KD   = largeur_de_bande_-1;           // upper bandwidth
  int LDAB = largeur_de_bande_;             //n_;// number of rows of abd_
  int LDB  = n;                             //m_;// number of rows of b
  int NRHS = 1;                             // number of columns of b (= vector)
  int INFO = 0;
 
  // solve the system
  F77NAME(DPBTRS)(&UPLO, &n, &KD, &NRHS, matrice_bande_factorisee_fortran_.addr() , &LDAB, vecteur.addr(), &LDB, &INFO);
 
  if(INFO)
    {
      Cerr << "Solv_Cholesky::resoudre_systeme error : ";
      if(INFO<0) Cerr << "F77NAME(DPBTRS) param. " << -INFO << " invalid" << finl;
      if(INFO>0) Cerr << "singular matrix ! resolution not possible" << finl;
      exit();
    };
  // inverse permutation of the result
  // subroutine dvperm (n, x, perm)
  // SPARSKIT2/FORMATS/unary.f
  F77NAME(DVPERM)(&n, vecteur.addr(), matrice.permutation_inverse().addr());
 
  solution = vecteur;
  solution.echange_espace_virtuel();
  //   test
  //   DoubleVect res;
  //   Cout<<"second membre "<<secmem.norme()<<finl;
  //   Cout<<"solution "<<solution.norme()<<finl;
  //   res = matrice*solution - secmem;
  //   Cout<<"residu "<<res.norme()<<finl;
 
  return 1;
}
 
 
 
int Solv_Cholesky::Fact_Cholesky(const Matrice_Morse_Sym& mat1, const int size_reelle)
{
  largeur_de_bande_ = mat1.largeur_de_bande();
  // store the matrix in FORTRAN band format
  matrice_bande_factorisee_fortran_.resize_array(size_reelle*largeur_de_bande_);
 
  for (int j=0; j<size_reelle; j++)
    {
      int  i;
      i = j+1 - largeur_de_bande_;
      int k = 0;
      while (k < largeur_de_bande_)
        {
          if (i >= 0)
            {
              //Cout<<"i j "<<i<<" "<<j<<" "<<mat1(i,j)<<" "<<me()<<finl;
              const double tmpa = mat1(i,j);
              matrice_bande_factorisee_fortran_[j * largeur_de_bande_ + k] = tmpa;
            }
 
          i++;
          k++;
        }
    }
 
  // Cholesky factorization
 
  // int DBG=1;
  // int PRC=0;
  char UPLO = 'U';
  int N = size_reelle;
  int KD = largeur_de_bande_ - 1;// mu: number of super-diagonals
  int LDAB = largeur_de_bande_; //n_
  int INFO = 0;
 
 
  Cerr << "Starting factorisation ..." << finl;
  F77NAME(DPBTRF)(&UPLO, &N, &KD,
                  matrice_bande_factorisee_fortran_.addr() , &LDAB, &INFO);
  Cerr << "End factorization." << finl;
 
  //   {
  //     double ANORM=1.0;
  //     double RCOND;
  //     ArrOfDouble WORK(3*N);
  //     ArrOfInt IWORK(N);
  //     F77NAME(DPBCON)(&UPLO, &N, &KD,
  //                     matrice_bande_factorisee_fortran_.addr() , &LDAB,
  //                     &ANORM, &RCOND, WORK.addr(), IWORK.addr(), &INFO);
  //     Cerr<<"//////////// RCOND : "<<RCOND<<finl;
  //   }
  if(INFO)
    {
      Cerr << "Solv_Cholesky::Fact_Cholesky() error : ";
      if(INFO<0) Cerr << "F77NAME(DPBTRF) param. " << -INFO
                        << " invalid" << finl;
      if(INFO>0) Cerr << "submatrix of order " << INFO
                        << " not positive definite!" << finl;
      if (INFO<100)
        {
          for (int i=0; i<INFO; i++)
            Cerr << "A(" <<i<<","<<i<<")="<<mat1(i,i)<<finl;
          Cerr << "non-positive definite matrix ="<<finl;
          mat1.imprimer_formatte(Cerr);
        }
      exit();
    };
 
  // TODO: could free matrice and matrice_renumerotee here
  return 1;
 
}