Ginkgo Generated from branch based on main. Ginkgo version 1.9.0
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#include <ginkgo/core/base/array.hpp>
12#include <ginkgo/core/base/exception_helpers.hpp>
13#include <ginkgo/core/base/lin_op.hpp>
14#include <ginkgo/core/base/math.hpp>
15#include <ginkgo/core/base/types.hpp>
16#include <ginkgo/core/config/config.hpp>
17#include <ginkgo/core/config/registry.hpp>
18#include <ginkgo/core/log/logger.hpp>
19#include <ginkgo/core/matrix/dense.hpp>
20#include <ginkgo/core/matrix/identity.hpp>
21#include <ginkgo/core/solver/solver_base.hpp>
22#include <ginkgo/core/stop/combined.hpp>
23#include <ginkgo/core/stop/criterion.hpp>
24
25
26namespace gko {
27namespace solver {
28
29
30[[deprecated]] constexpr size_type default_krylov_dim = 100u;
31
32constexpr size_type gmres_default_krylov_dim = 100u;
33
34namespace gmres {
38enum class ortho_method {
42 mgs,
46 cgs,
50 cgs2
51};
52
54std::ostream& operator<<(std::ostream& stream, ortho_method ortho);
55
56} // namespace gmres
57
71template <typename ValueType = default_precision>
72class Gmres
73 : public EnableLinOp<Gmres<ValueType>>,
74 public EnablePreconditionedIterativeSolver<ValueType, Gmres<ValueType>>,
75 public Transposable {
76 friend class EnableLinOp<Gmres>;
77 friend class EnablePolymorphicObject<Gmres, LinOp>;
78
79public:
80 using value_type = ValueType;
82
83 std::unique_ptr<LinOp> transpose() const override;
84
85 std::unique_ptr<LinOp> conj_transpose() const override;
86
92 bool apply_uses_initial_guess() const override { return true; }
93
99 size_type get_krylov_dim() const { return parameters_.krylov_dim; }
100
106 void set_krylov_dim(size_type other) { parameters_.krylov_dim = other; }
107
108
109 class Factory;
110
113 parameters_type, Factory> {
116
119
121 gmres::ortho_method GKO_FACTORY_PARAMETER_SCALAR(
122 ortho_method, gmres::ortho_method::mgs);
123 };
126
140 static parameters_type parse(const config::pnode& config,
141 const config::registry& context,
142 const config::type_descriptor& td_for_child =
143 config::make_type_descriptor<ValueType>());
144
145protected:
146 void apply_impl(const LinOp* b, LinOp* x) const override;
147
148 template <typename VectorType>
149 void apply_dense_impl(const VectorType* b, VectorType* x) const;
150
151 void apply_impl(const LinOp* alpha, const LinOp* b, const LinOp* beta,
152 LinOp* x) const override;
153
154 explicit Gmres(std::shared_ptr<const Executor> exec)
155 : EnableLinOp<Gmres>(std::move(exec))
156 {}
157
158 explicit Gmres(const Factory* factory,
159 std::shared_ptr<const LinOp> system_matrix)
160 : EnableLinOp<Gmres>(factory->get_executor(),
161 gko::transpose(system_matrix->get_size())),
162 EnablePreconditionedIterativeSolver<ValueType, Gmres<ValueType>>{
163 std::move(system_matrix), factory->get_parameters()},
164 parameters_{factory->get_parameters()}
165 {
166 if (!parameters_.krylov_dim) {
167 parameters_.krylov_dim = gmres_default_krylov_dim;
168 }
169 }
170};
171
172
173template <typename ValueType>
174struct workspace_traits<Gmres<ValueType>> {
175 using Solver = Gmres<ValueType>;
176 // number of vectors used by this workspace
177 static int num_vectors(const Solver&);
178 // number of arrays used by this workspace
179 static int num_arrays(const Solver&);
180 // array containing the num_vectors names for the workspace vectors
181 static std::vector<std::string> op_names(const Solver&);
182 // array containing the num_arrays names for the workspace vectors
183 static std::vector<std::string> array_names(const Solver&);
184 // array containing all varying scalar vectors (independent of problem size)
185 static std::vector<int> scalars(const Solver&);
186 // array containing all varying vectors (dependent on problem size)
187 static std::vector<int> vectors(const Solver&);
188
189 // residual vector
190 constexpr static int residual = 0;
191 // preconditioned vector
192 constexpr static int preconditioned_vector = 1;
193 // krylov basis multivector
194 constexpr static int krylov_bases = 2;
195 // hessenberg matrix
196 constexpr static int hessenberg = 3;
197 // auxiliary space for CGS2
198 constexpr static int hessenberg_aux = 4;
199 // givens sin parameters
200 constexpr static int givens_sin = 5;
201 // givens cos parameters
202 constexpr static int givens_cos = 6;
203 // coefficients of the residual in Krylov space
204 constexpr static int residual_norm_collection = 7;
205 // residual norm scalar
206 constexpr static int residual_norm = 8;
207 // solution of the least-squares problem in Krylov space
208 constexpr static int y = 9;
209 // solution of the least-squares problem mapped to the full space
210 constexpr static int before_preconditioner = 10;
211 // preconditioned solution of the least-squares problem
212 constexpr static int after_preconditioner = 11;
213 // constant 1.0 scalar
214 constexpr static int one = 12;
215 // constant -1.0 scalar
216 constexpr static int minus_one = 13;
217 // temporary norm vector of next_krylov to copy into hessenberg matrix
218 constexpr static int next_krylov_norm_tmp = 14;
219 // preconditioned krylov basis multivector
220 constexpr static int preconditioned_krylov_bases = 15;
221
222 // stopping status array
223 constexpr static int stop = 0;
224 // reduction tmp array
225 constexpr static int tmp = 1;
226 // final iteration number array
227 constexpr static int final_iter_nums = 2;
228};
229
230
231} // namespace solver
232} // namespace gko
233
234
235#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:879
This mixin inherits from (a subclass of) PolymorphicObject and provides a base implementation of a ne...
Definition polymorphic_object.hpp:662
Definition lin_op.hpp:117
const dim< 2 > & get_size() const noexcept
Returns the size of the operator.
Definition lin_op.hpp:210
std::shared_ptr< const Executor > get_executor() const noexcept
Returns the Executor of the object.
Definition polymorphic_object.hpp:234
Linear operators which support transposition should implement the Transposable interface.
Definition lin_op.hpp:433
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:167
This class describes the value and index types to be used when building a Ginkgo type from a configur...
Definition type_descriptor.hpp:39
A LinOp implementing this interface stores a system matrix and stopping criterion factory.
Definition solver_base.hpp:787
Definition gmres.hpp:124
GMRES or the generalized minimal residual method is an iterative type Krylov subspace method which is...
Definition gmres.hpp:75
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:99
bool apply_uses_initial_guess() const override
Return true as iterative solvers use the data in x as an initial guess.
Definition gmres.hpp:92
void set_krylov_dim(size_type other)
Sets the Krylov dimension.
Definition gmres.hpp:106
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:1017
The Ginkgo namespace.
Definition abstract_factory.hpp:20
constexpr T one()
Returns the multiplicative identity for T.
Definition math.hpp:630
std::size_t size_type
Integral type used for allocation quantities.
Definition types.hpp:89
STL namespace.
Definition gmres.hpp:113
size_type krylov_dim
Krylov subspace dimension/restart value.
Definition gmres.hpp:115
gmres::ortho_method ortho_method
Orthogonalization method.
Definition gmres.hpp:122
bool flexible
Flexible GMRES.
Definition gmres.hpp:118
Traits class providing information on the type and location of workspace vectors inside a solver.
Definition solver_base.hpp:238