Ginkgo: ginkgo/core/base/matrix_assembly_data.hpp Source File

| Ginkgo Generated from branch based on main. Ginkgo version 1.11.0 A numerical linear algebra library targeting many-core architectures

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matrix_assembly_data.hpp
1// SPDX-FileCopyrightText: 2017 - 2025 The Ginkgo authors
2//
3// SPDX-License-Identifier: BSD-3-Clause
4
5#ifndef GKO_PUBLIC_CORE_BASE_MATRIX_ASSEMBLY_DATA_HPP_
6#define GKO_PUBLIC_CORE_BASE_MATRIX_ASSEMBLY_DATA_HPP_
7
8
9#include <algorithm>
10#include <iterator>
11#include <numeric>
12#include <tuple>
13#include <unordered_map>
14
15#include <ginkgo/core/base/dim.hpp>
16#include <ginkgo/core/base/math.hpp>
17#include <ginkgo/core/base/matrix_data.hpp>
18#include <ginkgo/core/base/types.hpp>
19#include <ginkgo/core/base/utils.hpp>
20
21
22namespace gko {
23namespace detail {
24
25
26template <typename IndexType>
27struct symbolic_nonzero_hash {
28 symbolic_nonzero_hash() = default;
29
30 explicit symbolic_nonzero_hash(size_type num_cols) noexcept
31 : num_cols_{num_cols}
32 {}
33
34 std::size_t operator()(std::pair<IndexType, IndexType> nnz) const noexcept
35 {
36 return static_cast<std::size_t>(nnz.first) * num_cols_ + nnz.second;
37 }
38
39 size_type num_cols_;
40};
41
42
43} // namespace detail
44
45
58template <typename ValueType = default_precision, typename IndexType = int32>
59 class matrix_assembly_data {
60 GKO_ASSERT_SUPPORTED_VALUE_TYPE;
61
62public:
63 using value_type = ValueType;
64 using index_type = IndexType;
65
66 explicit matrix_assembly_data(dim<2> size)
67 : size_{size},
68 nonzeros_(0, detail::symbolic_nonzero_hash<index_type>(size_[1]))
69 {}
70
80 void add_value(index_type row, index_type col, value_type val)
81 {
82 auto ind = std::make_pair(row, col);
83 nonzeros_[ind] += val;
84 }
85
94 void set_value(index_type row, index_type col, value_type val)
95 {
96 auto ind = std::make_pair(row, col);
97 nonzeros_[ind] = val;
98 }
99
107 value_type get_value(index_type row, index_type col)
108 {
109 const auto it = nonzeros_.find(std::make_pair(row, col));
110 if (it == nonzeros_.end()) {
111 return zero<value_type>();
112 } else {
113 return it->second;
114 }
115 }
116
124 bool contains(index_type row, index_type col)
125 {
126 return nonzeros_.find(std::make_pair(row, col)) != nonzeros_.end();
127 }
128
130 dim<2> get_size() const noexcept { return size_; }
131
133 size_type get_num_stored_elements() const noexcept
134 {
135 return nonzeros_.size();
136 }
137
142 matrix_data<ValueType, IndexType> get_ordered_data() const
143 {
144 using output_type = matrix_data<ValueType, IndexType>;
145 using nonzero_type = typename output_type::nonzero_type;
146 using entry_type =
147 std::pair<std::pair<index_type, index_type>, value_type>;
148 output_type data{size_};
149 data.nonzeros.reserve(nonzeros_.size());
150 std::transform(nonzeros_.begin(), nonzeros_.end(),
151 std::back_inserter(data.nonzeros), [](entry_type entry) {
152 return nonzero_type{entry.first.first,
153 entry.first.second,
154 entry.second};
155 });
156 data.sort_row_major();
157 return data;
158 }
159
160private:
164 dim<2> size_;
165
173 std::unordered_map<std::pair<index_type, index_type>, value_type,
174 detail::symbolic_nonzero_hash<index_type>>
175 nonzeros_;
176};
177
178
179} // namespace gko
180
181
182#endif // GKO_PUBLIC_CORE_BASE_MATRIX_ASSEMBLY_DATA_HPP_
gko::matrix_assembly_data::add_value
void add_value(index_type row, index_type col, value_type val)
Sets the matrix value at (row, col).
Definition matrix_assembly_data.hpp:80
gko::matrix_assembly_data::set_value
void set_value(index_type row, index_type col, value_type val)
Sets the matrix value at (row, col).
Definition matrix_assembly_data.hpp:94
gko::matrix_assembly_data::get_num_stored_elements
size_type get_num_stored_elements() const noexcept
Definition matrix_assembly_data.hpp:133
gko::matrix_assembly_data::contains
bool contains(index_type row, index_type col)
Returns true iff the matrix contains an entry at (row, col).
Definition matrix_assembly_data.hpp:124
gko::matrix_assembly_data::get_value
value_type get_value(index_type row, index_type col)
Gets the matrix value at (row, col).
Definition matrix_assembly_data.hpp:107
gko::matrix_assembly_data::get_size
dim< 2 > get_size() const noexcept
Definition matrix_assembly_data.hpp:130
gko::matrix_assembly_data::get_ordered_data
matrix_data< ValueType, IndexType > get_ordered_data() const
Definition matrix_assembly_data.hpp:142
gko
The Ginkgo namespace.
Definition abstract_factory.hpp:20
gko::zero
constexpr T zero()
Returns the additive identity for T.
Definition math.hpp:626
gko::size_type
std::size_t size_type
Integral type used for allocation quantities.
Definition types.hpp:90
gko::dim
A type representing the dimensions of a multidimensional object.
Definition dim.hpp:26
gko::matrix_data
This structure is used as an intermediate data type to store a sparse matrix.
Definition matrix_data.hpp:126
gko::matrix_data::nonzeros
std::vector< nonzero_type > nonzeros
A vector of tuples storing the non-zeros of the matrix.
Definition matrix_data.hpp:454