text: /* 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., 51 Franklin Street, Fifth Floor, Boston, MA
      02110-1301  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>
  
  /**
   * 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 );
  }
  