office-gobmx/hwpfilter/source/solver.cxx
2011-06-13 23:20:18 +01:00

187 lines
4.1 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*************************************************************************
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* Copyright 2000, 2010 Oracle and/or its affiliates.
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* only, as published by the Free Software Foundation.
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License version 3 for more details
* (a copy is included in the LICENSE file that accompanied this code).
*
* You should have received a copy of the GNU Lesser General Public License
* version 3 along with OpenOffice.org. If not, see
* <http://www.openoffice.org/license.html>
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#include <math.h>
#include "solver.h"
//---------------------------------------------------------------------------
double** mgcLinearSystemD::NewMatrix (int N)
{
double** A = new double*[N];
if ( !A )
return 0;
for (int row = 0; row < N; row++)
{
A[row] = new double[N];
if ( !A[row] )
{
for (int i = 0; i < row; i++)
delete[] A[i];
delete[] A;
return 0;
}
for (int col = 0; col < N; col++)
A[row][col] = 0;
}
return A;
}
//---------------------------------------------------------------------------
void mgcLinearSystemD::DeleteMatrix (int N, double** A)
{
for (int row = 0; row < N; row++)
delete[] A[row];
delete[] A;
}
//---------------------------------------------------------------------------
double* mgcLinearSystemD::NewVector (int N)
{
double* B = new double[N];
if ( !B )
return 0;
for (int row = 0; row < N; row++)
B[row] = 0;
return B;
}
//---------------------------------------------------------------------------
int mgcLinearSystemD::Solve (int n, double** a, double* b)
{
int* indxc = new int[n];
if ( !indxc )
return 0;
int* indxr = new int[n];
if ( !indxr ) {
delete[] indxc;
return 0;
}
int* ipiv = new int[n];
if ( !ipiv ) {
delete[] indxc;
delete[] indxr;
return 0;
}
int i, j, k;
int irow = 0;
int icol = 0;
double big, pivinv, save;
for (j = 0; j < n; j++)
ipiv[j] = 0;
for (i = 0; i < n; i++)
{
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 )
{
delete[] ipiv;
delete[] indxr;
delete[] indxc;
return 0;
}
}
}
}
ipiv[icol]++;
if ( irow != icol )
{
double* rowptr = a[irow];
a[irow] = a[icol];
a[icol] = rowptr;
save = b[irow];
b[irow] = b[icol];
b[icol] = save;
}
indxr[i] = irow;
indxc[i] = icol;
if ( a[icol][icol] == 0 )
{
delete[] ipiv;
delete[] indxr;
delete[] indxc;
return 0;
}
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;
}
}
}
delete[] ipiv;
delete[] indxr;
delete[] indxc;
return 1;
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */