blob: 9bfac27385409eac5862d9fa068fc0c8697b517f [file] [log] [blame]
/* matrix/submatrix_source.c
*
* Copyright (C) 1996, 1997, 1998, 1999, 2000 Gerard Jungman, Brian Gough
*
* This program 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 2 of the License, or (at
* your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
QUALIFIED_VIEW(_gsl_matrix,view)
FUNCTION (gsl_matrix, submatrix) (QUALIFIED_TYPE(gsl_matrix) * m,
const size_t i, const size_t j,
const size_t n1, const size_t n2)
{
QUALIFIED_VIEW(_gsl_matrix,view) view = NULL_MATRIX_VIEW;
if (i >= m->size1)
{
GSL_ERROR_VAL ("row index is out of range", GSL_EINVAL, view);
}
else if (j >= m->size2)
{
GSL_ERROR_VAL ("column index is out of range", GSL_EINVAL, view);
}
else if (n1 == 0)
{
GSL_ERROR_VAL ("first dimension must be non-zero", GSL_EINVAL, view);
}
else if (n2 == 0)
{
GSL_ERROR_VAL ("second dimension must be non-zero", GSL_EINVAL, view);
}
else if (i + n1 > m->size1)
{
GSL_ERROR_VAL ("first dimension overflows matrix", GSL_EINVAL, view);
}
else if (j + n2 > m->size2)
{
GSL_ERROR_VAL ("second dimension overflows matrix", GSL_EINVAL, view);
}
{
TYPE(gsl_matrix) s = NULL_MATRIX;
s.data = m->data + MULTIPLICITY * (i * m->tda + j);
s.size1 = n1;
s.size2 = n2;
s.tda = m->tda;
s.block = m->block;
s.owner = 0;
view.matrix = s;
return view;
}
}