Solv_GCP.h

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#ifndef Solv_GCP_included
#define Solv_GCP_included
 
#include <Matrice_SuperMorse.h>
#include <Matrice_Morse_Sym.h>
#include <solv_iteratif.h>
#include <Precond_base.h>
#include <TRUST_Deriv.h>
 
class Solv_GCP: public solv_iteratif
{
  Declare_instanciable_sans_constructeur(Solv_GCP);
public:
  Solv_GCP();
  int resoudre_systeme(const Matrice_Base&, const DoubleVect&, DoubleVect&) override;
  int resoudre_systeme(const Matrice_Base&, const DoubleVect&, DoubleVect&, int) override;
  inline const OWN_PTR(Precond_base)& get_precond() const { return le_precond_; }
  inline OWN_PTR(Precond_base)& get_precond() { return le_precond_; }
  inline void set_precond(const OWN_PTR(Precond_base)& pre) { le_precond_ = pre; }
  void reinit() override;
  int supporte_matrice_morse_sym() override
  {
    return !le_precond_ || le_precond_->supporte_matrice_morse_sym();
  }
  // GCP does not need that b has an updated virtual space...
  int get_flag_updated_input() const override { return 0; }
 
protected:
  void prepare_data(const Matrice_Base& matrice, const DoubleVect& secmem, DoubleVect& solution);
  int resoudre_(const Matrice_Base&, const DoubleVect&, DoubleVect&, int);
 
  bool optimized_ = false;
  OWN_PTR(Precond_base) le_precond_;
  // Data file parameter: should we apply global diagonal preconditioning?
  // In that case, the matrix is copied and multiplied on the left and right by 1/sqrt(diagonal)
  // and the right-hand side and solution are similarly scaled.
  // (Warning: this changes the inner product metric and thus the interpretation of the threshold):
  //     A * X = B
  // <=> D * A * X = D * B    (with D = 1 / sqrt(diagonal))
  // <=> (D * A * D) * Y = D * B, and X = D * Y
  // Property: the diagonal entries of D * A * D are equal to 1
  bool precond_diag_ = false;
  // A vector with virtual items
  DoubleVect tmp_p_avec_items_virt_;
  // Four vectors without virtual items (one could add virtual spaces to all vectors,
  // but this saves space in the cache).
  DoubleVect resu_;
  DoubleVect residu_;
  // tmp_p_ points to the same memory region as tmp_p_avec_items_virt_
  // (this alias is created because vector operations check that
  //  sizes and parallel structures are identical,
  //  e.g. for the preconditioner...)
  DoubleVect tmp_p_;
  DoubleVect tmp_solution_;
  // Matrix of real-real coefficients
  Matrice_Morse_Sym tmp_mat_;
  // Matrix of real-virtual coefficients (storage without empty rows)
  Matrice_SuperMorse tmp_mat_virt_;
  // Memory block holding temporary vectors and possibly matrices
  // (do not read from it directly: it also contains integers!)
  // Using double to ensure correct memory alignment
  ArrOfDouble tmp_data_block_;
  // Renumbering table between the RHS and the temporary vectors
  // (removal of shared and unused virtual items)
  IntVect renum_;
  // If diagonal preconditioning is to be applied,
  // inverse of the square root of the diagonal coefficients of the matrix
  // Warning: the virtual space of this vector is updated because it is needed
  // for D*A*D
  DoubleVect inv_sqrt_diag_;
  int reinit_ = 0; // 0=> nothing ready, 1=> memory allocated, matrix coeffs to copy, 2=> ok
  int nb_it_max_ = -1;
};
 
#endif /* Solv_GCP_included */