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extractMatrix.hpp
/*
Copyright 2021 SINTEF Digital, Mathematics and Cybernetics.
This file is part of the Open Porous Media project (OPM).
OPM is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
OPM is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with OPM. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef OPM_EXTRACT_MATRIX_HEADER_INCLUDED
#define OPM_EXTRACT_MATRIX_HEADER_INCLUDED
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <vector>
namespace Opm
{
namespace Details
{
template <class Matrix>
void copySubMatrix(const Matrix& A, const std::vector<int>& indices, Matrix& B)
{
// Copy elements so that B_{i, j} = A_{indices[i], indices[j]}.
for (auto row = B.begin(); row != B.end(); ++row) {
for (auto col = row->begin(); col != row->end(); ++col) {
*col = A[indices[row.index()]][indices[col.index()]];
}
}
}
template <class Matrix>
Matrix extractMatrix(const Matrix& m, const std::vector<int>& indices)
{
assert(std::is_sorted(indices.begin(), indices.end()));
// Set up reverse index map.
const std::size_t n = indices.size();
std::size_t newrow = 0;
enum { NotIncluded = -1 };
std::vector<int> index_map(m.N(), NotIncluded);
for (auto row = m.begin(); row != m.end(); ++row) {
const int row_index = row.index();
if (row_index == indices[newrow]) {
index_map[row_index] = newrow;
++newrow;
if (newrow == n) {
break;
}
}
}
assert(newrow == n);
// Count nonzeroes.
std::size_t nnz = 0;
for (auto row = m.begin(); row != m.end(); ++row) {
if (index_map[row.index()] != NotIncluded) {
for (auto col = row->begin(); col != row->end(); ++col) {
if (index_map[col.index()] != NotIncluded) {
++nnz;
}
}
}
}
// Create the matrix structure.
Matrix res(n, n, nnz, Matrix::row_wise);
auto from_row = m.begin();
for (auto row = res.createbegin(); row != res.createend(); ++row) {
// Move from_row to point to the row to be extracted.
while (static_cast<int>(from_row.index()) < indices[row.index()]) {
++from_row;
}
assert(static_cast<int>(from_row.index()) == indices[row.index()]);
// Insert nonzeros for row.
for (auto from_col = from_row->begin(); from_col != from_row->end(); ++from_col) {
const int new_col = index_map[from_col.index()];
if (new_col != NotIncluded) {
row.insert(new_col);
}
}
}
copySubMatrix(m, indices, res);
return res;
}
template <class Vector>
Vector extractVector(const Vector& x, const std::vector<int>& indices)
{
Vector res(indices.size());
for (std::size_t ii = 0; ii < indices.size(); ++ii) {
res[ii] = x[indices[ii]];
}
return res;
}
template <class Vector>
void setGlobal(const Vector& x, const std::vector<int>& indices, Vector& global_x)
{
for (std::size_t ii = 0; ii < indices.size(); ++ii) {
global_x[indices[ii]] = x[ii];
}
}
template <class Matrix>
bool matrixEqual(const Matrix& m1, const Matrix& m2)
{
// Compare size and nonzeroes.
if (m1.N() != m2.N()) return false;
if (m1.M() != m2.M()) return false;
if (m1.nonzeroes() != m2.nonzeroes()) return false;
auto row1 = m1.begin();
auto row2 = m2.begin();
for (; row1 != m1.end(); ++row1, ++row2) {
if (row2 == m2.end()) return false;
if (row1.index() != row2.index()) return false;
auto col1 = row1->begin();
auto col2 = row2->begin();
for (; col1 != row1->end(); ++col1, ++col2) {
if (col2 == row2->end()) return false;
if (col1.index() != col2.index()) return false;
if (*col1 != *col2) return false;
}
}
return true;
}
} // namespace Details
} // namespace Opm
#endif // OPM_EXTRACT_MATRIX_HEADER_INCLUDED
Opm
This file contains a set of helper functions used by VFPProd / VFPInj.
Definition blackoilbioeffectsmodules.hh:43