preconditioner.h

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#ifndef MUI_PRECONDITIONER_H_
#define MUI_PRECONDITIONER_H_
 
namespace mui {
namespace linalg {
 
// Base preconditioner class
template<typename ITYPE, typename VTYPE>
class preconditioner {
 
    public:
        // Abstract function on preconditioner apply
        virtual sparse_matrix<ITYPE,VTYPE> apply(const sparse_matrix<ITYPE,VTYPE> &) = 0;
        // Destructor
        virtual ~preconditioner(){};
};
 
// Class of Incomplete LU preconditioner
template<typename ITYPE, typename VTYPE>
class incomplete_lu_preconditioner : public preconditioner<ITYPE,VTYPE> {
 
    public:
        // Constructor
        incomplete_lu_preconditioner(const sparse_matrix<ITYPE,VTYPE>&);
        // Destructor
        ~incomplete_lu_preconditioner();
        // Member function on preconditioner apply
        sparse_matrix<ITYPE,VTYPE> apply(const sparse_matrix<ITYPE,VTYPE>&);
 
    private:
        // Lower triangular matrix for Incomplete LU preconditioner
        sparse_matrix<ITYPE,VTYPE> L_;
        // Upper triangular matrix for Incomplete LU preconditioner
        sparse_matrix<ITYPE,VTYPE> U_;
 
};
 
// Class of Incomplete Cholesky preconditioner
template<typename ITYPE, typename VTYPE>
class incomplete_cholesky_preconditioner : public preconditioner<ITYPE,VTYPE> {
 
    public:
        // Constructor
        incomplete_cholesky_preconditioner(const sparse_matrix<ITYPE,VTYPE>&);
        // Destructor
        ~incomplete_cholesky_preconditioner();
        // Member function on preconditioner apply
        sparse_matrix<ITYPE,VTYPE> apply(const sparse_matrix<ITYPE,VTYPE>&);
 
    private:
        // Lower triangular matrix for Incomplete Cholesky preconditioner
        sparse_matrix<ITYPE,VTYPE> L_;
};
 
// Class of Symmetric Successive Over-relaxation preconditioner
template<typename ITYPE, typename VTYPE>
class symmetric_successive_over_relaxation_preconditioner : public preconditioner<ITYPE,VTYPE> {
 
    public:
        // Constructor
        symmetric_successive_over_relaxation_preconditioner(const sparse_matrix<ITYPE,VTYPE>&, VTYPE = 1.0);
        // Destructor
        ~symmetric_successive_over_relaxation_preconditioner();
        // Member function on preconditioner apply
        sparse_matrix<ITYPE,VTYPE> apply(const sparse_matrix<ITYPE,VTYPE>&);
 
    private:
        // The coefficient matrix of the matrix equation
        sparse_matrix<ITYPE,VTYPE> A_;
        // The relaxation parameter
        VTYPE omega_;
};
 
// Class of diagonal (Jacobi) preconditioner
template<typename ITYPE, typename VTYPE>
class diagonal_preconditioner : public preconditioner<ITYPE,VTYPE> {
 
    public:
        // Constructor
        diagonal_preconditioner(const sparse_matrix<ITYPE,VTYPE>&);
        // Destructor
        ~diagonal_preconditioner();
        // Member function on preconditioner apply
        sparse_matrix<ITYPE,VTYPE> apply(const sparse_matrix<ITYPE,VTYPE>&);
 
    private:
        // The inverse diagonal matrix
        sparse_matrix<ITYPE,VTYPE> inv_diag_;
 
};
 
} // linalg
} // mui
 
// Include implementations
#include "../linear_algebra/preconditioner_ilu.h"
#include "../linear_algebra/preconditioner_ic.h"
#include "../linear_algebra/preconditioner_ssor.h"
#include "../linear_algebra/preconditioner_diagonal.h"
 
#endif /* MUI_PRECONDITIONER_H_ */