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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isai.hpp
1// SPDX-FileCopyrightText: 2017 - 2024 The Ginkgo authors
2//
3// SPDX-License-Identifier: BSD-3-Clause
4
5#ifndef GKO_PUBLIC_CORE_PRECONDITIONER_ISAI_HPP_
6#define GKO_PUBLIC_CORE_PRECONDITIONER_ISAI_HPP_
7
8
9#include <memory>
10
11#include <ginkgo/core/base/composition.hpp>
12#include <ginkgo/core/base/exception_helpers.hpp>
13#include <ginkgo/core/base/executor.hpp>
14#include <ginkgo/core/base/lin_op.hpp>
15#include <ginkgo/core/config/config.hpp>
16#include <ginkgo/core/config/registry.hpp>
17#include <ginkgo/core/matrix/csr.hpp>
18#include <ginkgo/core/matrix/dense.hpp>
19
20
21namespace gko {
27namespace preconditioner {
28
29
36enum struct isai_type { lower, upper, general, spd };
37
78template <isai_type IsaiType, typename ValueType, typename IndexType>
79class Isai : public EnableLinOp<Isai<IsaiType, ValueType, IndexType>>,
80 public Transposable {
81 friend class EnableLinOp<Isai>;
82 friend class EnablePolymorphicObject<Isai, LinOp>;
83 friend class Isai<isai_type::general, ValueType, IndexType>;
84 friend class Isai<isai_type::lower, ValueType, IndexType>;
85 friend class Isai<isai_type::upper, ValueType, IndexType>;
86 friend class Isai<isai_type::spd, ValueType, IndexType>;
87
88public:
89 using value_type = ValueType;
90 using index_type = IndexType;
91 using transposed_type =
92 Isai<IsaiType == isai_type::general ? isai_type::general
93 : IsaiType == isai_type::spd ? isai_type::spd
94 : IsaiType == isai_type::lower ? isai_type::upper
95 : isai_type::lower,
96 ValueType, IndexType>;
97 using Comp = Composition<ValueType>;
98 using Csr = matrix::Csr<ValueType, IndexType>;
99 using Dense = matrix::Dense<ValueType>;
100 static constexpr isai_type type{IsaiType};
101
109 std::shared_ptr<const typename std::conditional<IsaiType == isai_type::spd,
110 Comp, Csr>::type>
112 {
113 return as<typename std::conditional<IsaiType == isai_type::spd, Comp,
114 Csr>::type>(approximate_inverse_);
115 }
116
122 Isai& operator=(const Isai& other);
123
130 Isai& operator=(Isai&& other);
131
136 Isai(const Isai& other);
137
143 Isai(Isai&& other);
144
146 {
156
166
179
186 std::shared_ptr<const LinOpFactory> GKO_DEFERRED_FACTORY_PARAMETER(
188
190 excess_solver_reduction,
191 static_cast<remove_complex<value_type>>(1e-6));
192 };
193
194 GKO_ENABLE_LIN_OP_FACTORY(Isai, parameters, Factory);
196
210 static parameters_type parse(
211 const config::pnode& config, const config::registry& context,
212 const config::type_descriptor& td_for_child =
213 config::make_type_descriptor<ValueType, IndexType>());
214
215 std::unique_ptr<LinOp> transpose() const override;
216
217 std::unique_ptr<LinOp> conj_transpose() const override;
218
219protected:
220 explicit Isai(std::shared_ptr<const Executor> exec)
221 : EnableLinOp<Isai>(std::move(exec))
222 {}
223
230 explicit Isai(const Factory* factory,
231 std::shared_ptr<const LinOp> system_matrix)
232 : EnableLinOp<Isai>(factory->get_executor(), system_matrix->get_size()),
233 parameters_{factory->get_parameters()}
234 {
235 const auto skip_sorting = parameters_.skip_sorting;
236 const auto power = parameters_.sparsity_power;
237 const auto excess_limit = parameters_.excess_limit;
238 generate_inverse(system_matrix, skip_sorting, power, excess_limit,
239 static_cast<remove_complex<value_type>>(
240 parameters_.excess_solver_reduction));
241 if (IsaiType == isai_type::spd) {
242 auto inv = share(as<Csr>(approximate_inverse_));
243 auto inv_transp = share(inv->conj_transpose());
244 approximate_inverse_ =
245 Composition<ValueType>::create(inv_transp, inv);
246 }
247 }
248
249 void apply_impl(const LinOp* b, LinOp* x) const override
250 {
251 approximate_inverse_->apply(b, x);
252 }
253
254 void apply_impl(const LinOp* alpha, const LinOp* b, const LinOp* beta,
255 LinOp* x) const override
256 {
257 approximate_inverse_->apply(alpha, b, beta, x);
258 }
259
260private:
271 void generate_inverse(std::shared_ptr<const LinOp> to_invert,
272 bool skip_sorting, int power, index_type excess_limit,
273 remove_complex<value_type> excess_solver_reduction);
274
275private:
276 std::shared_ptr<LinOp> approximate_inverse_;
277};
278
279
280template <typename ValueType = default_precision, typename IndexType = int32>
282
283template <typename ValueType = default_precision, typename IndexType = int32>
285
286template <typename ValueType = default_precision, typename IndexType = int32>
288
289template <typename ValueType = default_precision, typename IndexType = int32>
291
292
293} // namespace preconditioner
294} // namespace gko
295
296
297#endif // GKO_PUBLIC_CORE_PRECONDITIONER_ISAI_HPP_
The Composition class can be used to compose linear operators op1, op2, ..., opn and obtain the opera...
Definition composition.hpp:41
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
LinOp(const LinOp &)=default
Copy-constructs a LinOp.
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
CSR is a matrix format which stores only the nonzero coefficients by compressing each row of the matr...
Definition csr.hpp:121
Dense is a matrix format which explicitly stores all values of the matrix.
Definition dense.hpp:117
Definition isai.hpp:194
The Incomplete Sparse Approximate Inverse (ISAI) Preconditioner generates an approximate inverse matr...
Definition isai.hpp:80
Isai(const Isai &other)
Copy-constructs an ISAI preconditioner.
std::unique_ptr< LinOp > transpose() const override
Returns a LinOp representing the transpose of the Transposable object.
static parameters_type parse(const config::pnode &config, const config::registry &context, const config::type_descriptor &td_for_child=config::make_type_descriptor< ValueType, IndexType >())
Create the parameters from the property_tree.
Isai & operator=(Isai &&other)
Move-assigns an ISAI preconditioner.
Isai(Isai &&other)
Move-constructs an ISAI preconditioner.
std::unique_ptr< LinOp > conj_transpose() const override
Returns a LinOp representing the conjugate transpose of the Transposable object.
std::shared_ptr< const typename std::conditional< IsaiType==isai_type::spd, Comp, Csr >::type > get_approximate_inverse() const
Returns the approximate inverse of the given matrix (either a CSR matrix for IsaiType general,...
Definition isai.hpp:111
Isai & operator=(const Isai &other)
Copy-assigns an ISAI preconditioner.
#define GKO_CREATE_FACTORY_PARAMETERS(_parameters_name, _factory_name)
This Macro will generate a new type containing the parameters for the factory _factory_name.
Definition abstract_factory.hpp:280
#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 Preconditioner namespace.
Definition gauss_seidel.hpp:19
isai_type
This enum lists the types of the ISAI preconditioner.
Definition isai.hpp:36
The Ginkgo namespace.
Definition abstract_factory.hpp:20
typename detail::remove_complex_s< T >::type remove_complex
Obtain the type which removed the complex of complex/scalar type or the template parameter of class b...
Definition math.hpp:260
std::size_t size_type
Integral type used for allocation quantities.
Definition types.hpp:89
std::decay_t< T > * as(U *obj)
Performs polymorphic type conversion.
Definition utils_helper.hpp:307
detail::shared_type< OwningPointer > share(OwningPointer &&p)
Marks the object pointed to by p as shared.
Definition utils_helper.hpp:224
STL namespace.
bool skip_sorting
Optimization parameter that skips the sorting of the input matrix (only skip if it is known that it i...
Definition isai.hpp:155
std::shared_ptr< const LinOpFactory > excess_solver_factory
Factory for the Excess System solver.
Definition isai.hpp:187
int sparsity_power
Which power of the input matrix should be used for the sparsity pattern.
Definition isai.hpp:165
size_type excess_limit
Size limit for the excess system.
Definition isai.hpp:178