libvips/libvips/mask/im_mattrn.c
2010-10-23 09:27:41 +00:00

90 lines
1.9 KiB
C

/* matrix transpose
*
* Copyright: 1990, K. Martinez and J. Cupitt
*
*/
/*
This file is part of VIPS.
VIPS is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser 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 Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#include <stdio.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/**
* im_mattrn:
* @in: input matrix
* @filename: name for output matrix
*
* Transposes the input matrix.
* Pass the filename to set for the output.
*
* See also: im_matmul(), im_matinv().
*
* Returns: the result matrix on success, or %NULL on error.
*/
DOUBLEMASK *
im_mattrn( DOUBLEMASK *in, const char *name )
{
int xc, yc;
DOUBLEMASK *mat;
double *out, *a, *b;
/* Allocate output matrix.
*/
if( !(mat = im_create_dmask( name, in->ysize, in->xsize )) )
return( NULL );
mat->scale = in->scale;
mat->offset = in->offset;
/* Transpose.
*/
out = mat->coeff;
a = in->coeff;
for( yc = 0; yc < mat->ysize; yc++ ) {
b = a;
for( xc = 0; xc < mat->xsize; xc++ ) {
*out++ = *b;
b += in->xsize;
}
a++;
}
return( mat );
}