Ginkgo Generated from branch based on master. Ginkgo version 1.8.0
A numerical linear algebra library targeting many-core architectures
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gmres.hpp
1// SPDX-FileCopyrightText: 2017 - 2024 The Ginkgo authors
2//
3// SPDX-License-Identifier: BSD-3-Clause
4
5#ifndef GKO_PUBLIC_CORE_SOLVER_GMRES_HPP_
6#define GKO_PUBLIC_CORE_SOLVER_GMRES_HPP_
7
8
9#include <vector>
10
11
12#include <ginkgo/core/base/array.hpp>
13#include <ginkgo/core/base/exception_helpers.hpp>
14#include <ginkgo/core/base/lin_op.hpp>
15#include <ginkgo/core/base/math.hpp>
16#include <ginkgo/core/base/types.hpp>
17#include <ginkgo/core/config/config.hpp>
18#include <ginkgo/core/config/registry.hpp>
19#include <ginkgo/core/log/logger.hpp>
20#include <ginkgo/core/matrix/dense.hpp>
21#include <ginkgo/core/matrix/identity.hpp>
22#include <ginkgo/core/solver/solver_base.hpp>
23#include <ginkgo/core/stop/combined.hpp>
24#include <ginkgo/core/stop/criterion.hpp>
25
26
27namespace gko {
28namespace solver {
29
30
31[[deprecated]] constexpr size_type default_krylov_dim = 100u;
32
33constexpr size_type gmres_default_krylov_dim = 100u;
34
35
49template <typename ValueType = default_precision>
50class Gmres
51 : public EnableLinOp<Gmres<ValueType>>,
52 public EnablePreconditionedIterativeSolver<ValueType, Gmres<ValueType>>,
53 public Transposable {
54 friend class EnableLinOp<Gmres>;
55 friend class EnablePolymorphicObject<Gmres, LinOp>;
56
57public:
58 using value_type = ValueType;
60
61 std::unique_ptr<LinOp> transpose() const override;
62
63 std::unique_ptr<LinOp> conj_transpose() const override;
64
70 bool apply_uses_initial_guess() const override { return true; }
71
77 size_type get_krylov_dim() const { return parameters_.krylov_dim; }
78
84 void set_krylov_dim(size_type other) { parameters_.krylov_dim = other; }
85
86
87 class Factory;
88
100
114 static parameters_type parse(const config::pnode& config,
115 const config::registry& context,
116 const config::type_descriptor& td_for_child =
117 config::make_type_descriptor<ValueType>());
118
119protected:
120 void apply_impl(const LinOp* b, LinOp* x) const override;
121
122 template <typename VectorType>
123 void apply_dense_impl(const VectorType* b, VectorType* x) const;
124
125 void apply_impl(const LinOp* alpha, const LinOp* b, const LinOp* beta,
126 LinOp* x) const override;
127
128 explicit Gmres(std::shared_ptr<const Executor> exec)
129 : EnableLinOp<Gmres>(std::move(exec))
130 {}
131
132 explicit Gmres(const Factory* factory,
133 std::shared_ptr<const LinOp> system_matrix)
134 : EnableLinOp<Gmres>(factory->get_executor(),
135 gko::transpose(system_matrix->get_size())),
136 EnablePreconditionedIterativeSolver<ValueType, Gmres<ValueType>>{
137 std::move(system_matrix), factory->get_parameters()},
138 parameters_{factory->get_parameters()}
139 {
140 if (!parameters_.krylov_dim) {
141 parameters_.krylov_dim = gmres_default_krylov_dim;
142 }
143 }
144};
145
146
147template <typename ValueType>
148struct workspace_traits<Gmres<ValueType>> {
149 using Solver = Gmres<ValueType>;
150 // number of vectors used by this workspace
151 static int num_vectors(const Solver&);
152 // number of arrays used by this workspace
153 static int num_arrays(const Solver&);
154 // array containing the num_vectors names for the workspace vectors
155 static std::vector<std::string> op_names(const Solver&);
156 // array containing the num_arrays names for the workspace vectors
157 static std::vector<std::string> array_names(const Solver&);
158 // array containing all varying scalar vectors (independent of problem size)
159 static std::vector<int> scalars(const Solver&);
160 // array containing all varying vectors (dependent on problem size)
161 static std::vector<int> vectors(const Solver&);
162
163 // residual vector
164 constexpr static int residual = 0;
165 // preconditioned vector
166 constexpr static int preconditioned_vector = 1;
167 // krylov basis multivector
168 constexpr static int krylov_bases = 2;
169 // hessenberg matrix
170 constexpr static int hessenberg = 3;
171 // givens sin parameters
172 constexpr static int givens_sin = 4;
173 // givens cos parameters
174 constexpr static int givens_cos = 5;
175 // coefficients of the residual in Krylov space
176 constexpr static int residual_norm_collection = 6;
177 // residual norm scalar
178 constexpr static int residual_norm = 7;
179 // solution of the least-squares problem in Krylov space
180 constexpr static int y = 8;
181 // solution of the least-squares problem mapped to the full space
182 constexpr static int before_preconditioner = 9;
183 // preconditioned solution of the least-squares problem
184 constexpr static int after_preconditioner = 10;
185 // constant 1.0 scalar
186 constexpr static int one = 11;
187 // constant -1.0 scalar
188 constexpr static int minus_one = 12;
189 // temporary norm vector of next_krylov to copy into hessenberg matrix
190 constexpr static int next_krylov_norm_tmp = 13;
191 // preconditioned krylov basis multivector
192 constexpr static int preconditioned_krylov_bases = 14;
193
194 // stopping status array
195 constexpr static int stop = 0;
196 // reduction tmp array
197 constexpr static int tmp = 1;
198 // final iteration number array
199 constexpr static int final_iter_nums = 2;
200};
201
202
203} // namespace solver
204} // namespace gko
205
206
207#endif // GKO_PUBLIC_CORE_SOLVER_GMRES_HPP_
The EnableLinOp mixin can be used to provide sensible default implementations of the majority of the ...
Definition lin_op.hpp:880
This mixin inherits from (a subclass of) PolymorphicObject and provides a base implementation of a ne...
Definition polymorphic_object.hpp:663
Definition lin_op.hpp:118
const dim< 2 > & get_size() const noexcept
Returns the size of the operator.
Definition lin_op.hpp:211
std::shared_ptr< const Executor > get_executor() const noexcept
Returns the Executor of the object.
Definition polymorphic_object.hpp:235
Linear operators which support transposition should implement the Transposable interface.
Definition lin_op.hpp:434
pnode describes a tree of properties.
Definition property_tree.hpp:28
This class stores additional context for creating Ginkgo objects from configuration files.
Definition registry.hpp:168
This class describes the value and index types to be used when building a Ginkgo type from a configur...
Definition type_descriptor.hpp:37
A LinOp implementing this interface stores a system matrix and stopping criterion factory.
Definition solver_base.hpp:788
Definition gmres.hpp:98
GMRES or the generalized minimal residual method is an iterative type Krylov subspace method which is...
Definition gmres.hpp:53
std::unique_ptr< LinOp > conj_transpose() const override
Returns a LinOp representing the conjugate transpose of the Transposable object.
std::unique_ptr< LinOp > transpose() const override
Returns a LinOp representing the transpose of the Transposable object.
size_type get_krylov_dim() const
Gets the Krylov dimension of the solver.
Definition gmres.hpp:77
bool apply_uses_initial_guess() const override
Return true as iterative solvers use the data in x as an initial guess.
Definition gmres.hpp:70
void set_krylov_dim(size_type other)
Sets the Krylov dimension.
Definition gmres.hpp:84
static parameters_type parse(const config::pnode &config, const config::registry &context, const config::type_descriptor &td_for_child=config::make_type_descriptor< ValueType >())
Create the parameters from the property_tree.
#define GKO_FACTORY_PARAMETER_SCALAR(_name, _default)
Creates a scalar factory parameter in the factory parameters structure.
Definition abstract_factory.hpp:445
#define GKO_ENABLE_BUILD_METHOD(_factory_name)
Defines a build method for the factory, simplifying its construction by removing the repetitive typin...
Definition abstract_factory.hpp:394
#define GKO_ENABLE_LIN_OP_FACTORY(_lin_op, _parameters_name, _factory_name)
This macro will generate a default implementation of a LinOpFactory for the LinOp subclass it is defi...
Definition lin_op.hpp:1018
The Ginkgo namespace.
Definition abstract_factory.hpp:20
constexpr T one()
Returns the multiplicative identity for T.
Definition math.hpp:775
std::size_t size_type
Integral type used for allocation quantities.
Definition types.hpp:86
size_type krylov_dim
Krylov subspace dimension/restart value.
Definition gmres.hpp:93
bool flexible
Flexible GMRES.
Definition gmres.hpp:96
Traits class providing information on the type and location of workspace vectors inside a solver.
Definition solver_base.hpp:239