ir.hpp

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#ifndef GKO_PUBLIC_CORE_SOLVER_IR_HPP_
#define GKO_PUBLIC_CORE_SOLVER_IR_HPP_
 
 
#include <vector>
 
 
#include <ginkgo/core/base/exception_helpers.hpp>
#include <ginkgo/core/base/lin_op.hpp>
#include <ginkgo/core/base/types.hpp>
#include <ginkgo/core/matrix/dense.hpp>
#include <ginkgo/core/matrix/identity.hpp>
#include <ginkgo/core/stop/combined.hpp>
#include <ginkgo/core/stop/criterion.hpp>
 
 
namespace gko {
namespace solver {
 
 
template <typename ValueType = default_precision>
class Ir : public EnableLinOp<Ir<ValueType>>, public Transposable {
    friend class EnableLinOp<Ir>;
    friend class EnablePolymorphicObject<Ir, LinOp>;
 
public:
    using value_type = ValueType;
    using transposed_type = Ir<ValueType>;
 
    std::shared_ptr<const LinOp> get_system_matrix() const
    {
        return system_matrix_;
    }
 
    std::unique_ptr<LinOp> transpose() const override;
 
    std::unique_ptr<LinOp> conj_transpose() const override;
 
    bool apply_uses_initial_guess() const override { return true; }
 
    std::shared_ptr<const LinOp> get_solver() const { return solver_; }
 
    void set_solver(std::shared_ptr<const LinOp> new_solver)
    {
        GKO_ASSERT_EQUAL_DIMENSIONS(new_solver, this);
        solver_ = new_solver;
    }
 
    std::shared_ptr<const stop::CriterionFactory> get_stop_criterion_factory()
        const
    {
        return stop_criterion_factory_;
    }
 
    void set_stop_criterion_factory(
        std::shared_ptr<const stop::CriterionFactory> other)
    {
        stop_criterion_factory_ = std::move(other);
    }
 
    GKO_CREATE_FACTORY_PARAMETERS(parameters, Factory)
    {
        std::vector<std::shared_ptr<const stop::CriterionFactory>>
            GKO_FACTORY_PARAMETER_VECTOR(criteria, nullptr);
 
        std::shared_ptr<const LinOpFactory> GKO_FACTORY_PARAMETER_SCALAR(
            solver, nullptr);
 
        std::shared_ptr<const LinOp> GKO_FACTORY_PARAMETER_SCALAR(
            generated_solver, nullptr);
 
        ValueType GKO_FACTORY_PARAMETER_SCALAR(relaxation_factor,
                                               value_type{1});
    };
    GKO_ENABLE_LIN_OP_FACTORY(Ir, parameters, Factory);
    GKO_ENABLE_BUILD_METHOD(Factory);
 
protected:
    void apply_impl(const LinOp *b, LinOp *x) const override;
 
    void apply_impl(const LinOp *alpha, const LinOp *b, const LinOp *beta,
                    LinOp *x) const override;
 
    explicit Ir(std::shared_ptr<const Executor> exec)
        : EnableLinOp<Ir>(std::move(exec))
    {}
 
    explicit Ir(const Factory *factory,
                std::shared_ptr<const LinOp> system_matrix)
        : EnableLinOp<Ir>(factory->get_executor(),
                          gko::transpose(system_matrix->get_size())),
          parameters_{factory->get_parameters()},
          system_matrix_{std::move(system_matrix)}
    {
        GKO_ASSERT_IS_SQUARE_MATRIX(system_matrix_);
        if (parameters_.generated_solver) {
            solver_ = parameters_.generated_solver;
            GKO_ASSERT_EQUAL_DIMENSIONS(solver_, this);
        } else if (parameters_.solver) {
            solver_ = parameters_.solver->generate(system_matrix_);
        } else {
            solver_ = matrix::Identity<ValueType>::create(this->get_executor(),
                                                          this->get_size());
        }
        relaxation_factor_ = gko::initialize<matrix::Dense<ValueType>>(
            {parameters_.relaxation_factor}, this->get_executor());
        stop_criterion_factory_ =
            stop::combine(std::move(parameters_.criteria));
    }
 
private:
    std::shared_ptr<const LinOp> system_matrix_{};
    std::shared_ptr<const LinOp> solver_{};
    std::shared_ptr<const stop::CriterionFactory> stop_criterion_factory_{};
    std::shared_ptr<const matrix::Dense<ValueType>> relaxation_factor_{};
};
 
 
template <typename ValueType = default_precision>
using Richardson = Ir<ValueType>;
 
 
}  // namespace solver
}  // namespace gko
 
 
#endif  // GKO_PUBLIC_CORE_SOLVER_IR_HPP_