source: Sophya/trunk/Poubelle/DPC:FitsIOServer/Blitz/blitz/tvcross.h@ 3997

/***************************************************************************
 * blitz/tvcross.h      Cross product of TinyVector<N,3>'s
 *
 * $Id: tvcross.h,v 1.1.1.1 1999-11-26 16:37:05 ansari Exp $
 *
 * Copyright (C) 1997,1998 Todd Veldhuizen <tveldhui@seurat.uwaterloo.ca>
 *
 * 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.
 *
 * Suggestions:          blitz-suggest@cybervision.com
 * Bugs:                 blitz-bugs@cybervision.com
 *
 * For more information, please see the Blitz++ Home Page:
 *    http://seurat.uwaterloo.ca/blitz/
 *
 ***************************************************************************
 * $Log: not supported by cvs2svn $
 * Revision 1.1.1.1  1999/04/09  17:59:02  ansari
 * Creation module DPC/Blitz (blitz 0.4) Reza 09/04/99
 *
 * Revision 1.1  1998/03/14 00:04:47  tveldhui
 * 0.2-alpha-05
 *
 */

#ifndef BZ_TVCROSS_H
#define BZ_TVCROSS_H

#ifndef BZ_TINYVEC_H
 #error <blitz/tvcross.h> must be included via <blitz/tinyvec.h>
#endif

BZ_NAMESPACE(blitz)

/*
 * cross product.
 *
 * NEEDS_WORK: - cross product of two different vector types
 *             - cross product involving expressions
 */

template<class T_numtype>
TinyVector<T_numtype,3> cross(const TinyVector<T_numtype,3>& x, 
    const TinyVector<T_numtype,3>& y)
{
    return TinyVector<T_numtype,3>(x[1]*y[2] - y[1]*x[2],
        y[0]*x[2] - x[0]*y[2], x[0]*y[1] - y[0]*x[1]);
}


BZ_NAMESPACE_END

#endif // BZ_TVCROSS_H