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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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
12#include <ginkgo/core/base/composition.hpp>
13#include <ginkgo/core/base/exception_helpers.hpp>
14#include <ginkgo/core/base/executor.hpp>
15#include <ginkgo/core/base/lin_op.hpp>
16#include <ginkgo/core/config/config.hpp>
17#include <ginkgo/core/config/registry.hpp>
18#include <ginkgo/core/matrix/csr.hpp>
19#include <ginkgo/core/matrix/dense.hpp>
20
21
22namespace gko {
28namespace preconditioner {
29
30
37enum struct isai_type { lower, upper, general, spd };
38
79template <isai_type IsaiType, typename ValueType, typename IndexType>
80class Isai : public EnableLinOp<Isai<IsaiType, ValueType, IndexType>>,
81 public Transposable {
82 friend class EnableLinOp<Isai>;
83 friend class EnablePolymorphicObject<Isai, LinOp>;
84 friend class Isai<isai_type::general, ValueType, IndexType>;
85 friend class Isai<isai_type::lower, ValueType, IndexType>;
86 friend class Isai<isai_type::upper, ValueType, IndexType>;
87 friend class Isai<isai_type::spd, ValueType, IndexType>;
88
89public:
90 using value_type = ValueType;
91 using index_type = IndexType;
92 using transposed_type =
93 Isai<IsaiType == isai_type::general ? isai_type::general
94 : IsaiType == isai_type::spd ? isai_type::spd
95 : IsaiType == isai_type::lower ? isai_type::upper
96 : isai_type::lower,
97 ValueType, IndexType>;
98 using Comp = Composition<ValueType>;
99 using Csr = matrix::Csr<ValueType, IndexType>;
100 using Dense = matrix::Dense<ValueType>;
101 static constexpr isai_type type{IsaiType};
102
110 std::shared_ptr<const typename std::conditional<IsaiType == isai_type::spd,
111 Comp, Csr>::type>
113 {
114 return as<typename std::conditional<IsaiType == isai_type::spd, Comp,
115 Csr>::type>(approximate_inverse_);
116 }
117
123 Isai& operator=(const Isai& other);
124
131 Isai& operator=(Isai&& other);
132
137 Isai(const Isai& other);
138
144 Isai(Isai&& other);
145
147 {
156 bool GKO_FACTORY_PARAMETER_SCALAR(skip_sorting, false);
157
166 int GKO_FACTORY_PARAMETER_SCALAR(sparsity_power, 1);
167
180
187 std::shared_ptr<const LinOpFactory> GKO_DEFERRED_FACTORY_PARAMETER(
188 excess_solver_factory);
189
191 excess_solver_reduction,
192 static_cast<remove_complex<value_type>>(1e-6));
193 };
194
197
212 const config::pnode& config, const config::registry& context,
213 const config::type_descriptor& td_for_child =
214 config::make_type_descriptor<ValueType, IndexType>());
215
216 std::unique_ptr<LinOp> transpose() const override;
217
218 std::unique_ptr<LinOp> conj_transpose() const override;
219
220protected:
221 explicit Isai(std::shared_ptr<const Executor> exec)
222 : EnableLinOp<Isai>(std::move(exec))
223 {}
224
231 explicit Isai(const Factory* factory,
232 std::shared_ptr<const LinOp> system_matrix)
233 : EnableLinOp<Isai>(factory->get_executor(), system_matrix->get_size()),
234 parameters_{factory->get_parameters()}
235 {
236 const auto skip_sorting = parameters_.skip_sorting;
237 const auto power = parameters_.sparsity_power;
238 const auto excess_limit = parameters_.excess_limit;
239 generate_inverse(system_matrix, skip_sorting, power, excess_limit,
240 static_cast<remove_complex<value_type>>(
241 parameters_.excess_solver_reduction));
242 if (IsaiType == isai_type::spd) {
243 auto inv = share(as<Csr>(approximate_inverse_));
244 auto inv_transp = share(inv->conj_transpose());
245 approximate_inverse_ =
246 Composition<ValueType>::create(inv_transp, inv);
247 }
248 }
249
250 void apply_impl(const LinOp* b, LinOp* x) const override
251 {
252 approximate_inverse_->apply(b, x);
253 }
254
255 void apply_impl(const LinOp* alpha, const LinOp* b, const LinOp* beta,
256 LinOp* x) const override
257 {
258 approximate_inverse_->apply(alpha, b, beta, x);
259 }
260
261private:
272 void generate_inverse(std::shared_ptr<const LinOp> to_invert,
273 bool skip_sorting, int power, index_type excess_limit,
274 remove_complex<value_type> excess_solver_reduction);
275
276private:
277 std::shared_ptr<LinOp> approximate_inverse_;
278};
279
280
281template <typename ValueType = default_precision, typename IndexType = int32>
282using LowerIsai = Isai<isai_type::lower, ValueType, IndexType>;
283
284template <typename ValueType = default_precision, typename IndexType = int32>
285using UpperIsai = Isai<isai_type::upper, ValueType, IndexType>;
286
287template <typename ValueType = default_precision, typename IndexType = int32>
288using GeneralIsai = Isai<isai_type::general, ValueType, IndexType>;
289
290template <typename ValueType = default_precision, typename IndexType = int32>
291using SpdIsai = Isai<isai_type::spd, ValueType, IndexType>;
292
293
294} // namespace preconditioner
295} // namespace gko
296
297
298#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: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
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: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
CSR is a matrix format which stores only the nonzero coefficients by compressing each row of the matr...
Definition sparsity_csr.hpp:22
Dense is a matrix format which explicitly stores all values of the matrix.
Definition sparsity_csr.hpp:26
Definition isai.hpp:195
The Incomplete Sparse Approximate Inverse (ISAI) Preconditioner generates an approximate inverse matr...
Definition isai.hpp:81
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:112
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:1018
isai_type
This enum lists the types of the ISAI preconditioner.
Definition isai.hpp:37
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:326
std::size_t size_type
Integral type used for allocation quantities.
Definition types.hpp:86
std::decay_t< T > * as(U *obj)
Performs polymorphic type conversion.
Definition utils_helper.hpp:309
detail::shared_type< OwningPointer > share(OwningPointer &&p)
Marks the object pointed to by p as shared.
Definition utils_helper.hpp:226
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:156
int sparsity_power
Which power of the input matrix should be used for the sparsity pattern.
Definition isai.hpp:166
size_type excess_limit
Size limit for the excess system.
Definition isai.hpp:179