dust3d/thirdparty/cgal/CGAL-5.1/include/CGAL/Polynomial/hgdelta_update.h

45 lines
1.3 KiB
C++

// Copyright (c) 2008 Max-Planck-Institute Saarbruecken (Germany)
//
// This file is part of CGAL (www.cgal.org)
//
// $URL: https://github.com/CGAL/cgal/blob/v5.1/Polynomial/include/CGAL/Polynomial/hgdelta_update.h $
// $Id: hgdelta_update.h 0779373 2020-03-26T13:31:46+01:00 Sébastien Loriot
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s) : Michael Hemmer
// ============================================================================
// TODO: The comments are all original EXACUS comments and aren't adapted. So
// they may be wrong now.
#ifndef CGAL_POLYNOMIAL_HGDELTA_UPDATE_H
#define CGAL_POLYNOMIAL_HGDELTA_UPDATE_H
namespace CGAL {
// This subroutine has been retained here for use in both new files.
namespace internal {
template <class NT> inline
void hgdelta_update(NT& h, const NT& g, int delta) {
typename Algebraic_structure_traits<NT>::Integral_division idiv;
// compute h = h^(1-delta) * g^delta
switch (delta) {
case 0:
// h = h;
break;
case 1:
h = g;
break;
default:
h = idiv(CGAL::ipower(g, delta), CGAL::ipower(h, delta-1));
break;
}
}
} // namespace internal
} //namespace CGAL
#endif // CGAL_POLYNOMIAL_HGDELTA_UPDATE_H