office-gobmx/hwpfilter/source/solver.cxx
Noel Grandin 976da2b60e loplugin:constparams in dbaccess..oox
Change-Id: I9c04906dd492c6f8a816f57f40bc31406a871a78
Reviewed-on: https://gerrit.libreoffice.org/66793
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
2019-01-24 07:46:46 +01:00

147 lines
3.2 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#include <math.h>
#include <memory>
#include "solver.h"
std::unique_ptr<std::unique_ptr<double[]>[]> mgcLinearSystemD::NewMatrix (int N)
{
std::unique_ptr<std::unique_ptr<double[]>[]> A(new std::unique_ptr<double[]>);
for (int row = 0; row < N; row++)
{
A[row].reset(new double[N]);
for (int col = 0; col < N; col++)
A[row][col] = 0;
}
return A;
}
std::unique_ptr<double[]> mgcLinearSystemD::NewVector (int N)
{
std::unique_ptr<double[]> B(new double[N]);
for (int row = 0; row < N; row++)
B[row] = 0;
return B;
}
bool mgcLinearSystemD::Solve (int n, std::unique_ptr<std::unique_ptr<double[]>[]> const & a, double* b)
{
std::unique_ptr<int[]> indxc( new int[n] );
if ( !indxc )
return false;
std::unique_ptr<int[]> indxr( new int[n] );
if ( !indxr ) {
return false;
}
std::unique_ptr<int[]> ipiv( new int[n] );
if ( !ipiv ) {
return false;
}
int i, j, k;
int irow = 0;
int icol = 0;
double save;
for (j = 0; j < n; j++)
ipiv[j] = 0;
for (i = 0; i < n; i++)
{
double big = 0;
for (j = 0; j < n; j++)
{
if ( ipiv[j] != 1 )
{
for (k = 0; k < n; k++)
{
if ( ipiv[k] == 0 )
{
if ( fabs(a[j][k]) >= big )
{
big = fabs(a[j][k]);
irow = j;
icol = k;
}
}
else if ( ipiv[k] > 1 )
{
return false;
}
}
}
}
ipiv[icol]++;
if ( irow != icol )
{
std::swap(a[irow], a[icol]);
save = b[irow];
b[irow] = b[icol];
b[icol] = save;
}
indxr[i] = irow;
indxc[i] = icol;
if ( a[icol][icol] == 0 )
{
return false;
}
double pivinv = 1/a[icol][icol];
a[icol][icol] = 1;
for (k = 0; k < n; k++)
a[icol][k] *= pivinv;
b[icol] *= pivinv;
for (j = 0; j < n; j++)
{
if ( j != icol )
{
save = a[j][icol];
a[j][icol] = 0;
for (k = 0; k < n; k++)
a[j][k] -= a[icol][k]*save;
b[j] -= b[icol]*save;
}
}
}
for (j = n-1; j >= 0; j--)
{
if ( indxr[j] != indxc[j] )
{
for (k = 0; k < n; k++)
{
save = a[k][indxr[j]];
a[k][indxr[j]] = a[k][indxc[j]];
a[k][indxc[j]] = save;
}
}
}
return true;
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */