URL: https://svn.lrde.epita.fr/svn/oln/trunk/milena ChangeLog: 2007-10-15 Guillaume Duhamel &lt;guillaume.duhamel(a)lrde.epita.fr&gt; Add norm l1. * l1.hh: New norm l1. --- l1.hh | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) Index: trunk/milena/mln/norm/l1.hh =================================================================== --- trunk/milena/mln/norm/l1.hh (revision 0) +++ trunk/milena/mln/norm/l1.hh (revision 1335) @@ -0,0 +1,120 @@ +// Copyright (C) 2007 EPITA Research and Development Laboratory +// +// This file is part of the Olena Library. This library is free +// software; you can redistribute it and/or modify it under the terms +// of the GNU General Public License version 2 as published by the +// Free Software Foundation. +// +// This library 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 library; see the file COPYING. If not, write to +// the Free Software Foundation, 51 Franklin Street, Fifth Floor, +// Boston, MA 02111-1307, USA. +// +// As a special exception, you may use this file as part of a free +// software library without restriction. Specifically, if other files +// instantiate templates or use macros or inline functions from this +// file, or you compile this file and link it with other files to +// produce an executable, this file does not by itself cause the +// resulting executable to be covered by the GNU General Public +// License. This exception does not however invalidate any other +// reasons why the executable file might be covered by the GNU General +// Public License. + +#ifndef MLN_NORM_L1_HH +# define MLN_NORM_L1_HH + +/*! \file mln/norm/l1.hh + * + * \brief Define some infinity-norm related routines. + */ + +# include <cmath> + +# include <mln/metal/vec.hh> + +namespace mln +{ + + namespace norm + { + + /// Infinity-norm of a vector \p vec. + template <unsigned n, typename C> + float l1(const C (&vec)[n]); + + /// Infinity-norm distance between vectors \p v1 and \p v2. + template <unsigned n, typename C> + float l1_distance(const C (&v1)[n], const C (&v2)[n]); + + template <unsigned n, typename C> + float l1(const metal::vec<n,C>& vec); + + template <unsigned n, typename C> + float l1_distance(const metal::vec<n,C>& vec1, const metal::vec<n,C>& vec2); + + // FIXME: Replace float by mln_value_sum(C)... + + +# ifndef MLN_INCLUDE_ONLY + + template <unsigned n, typename C> + float l1(const C (&vec)[n]) + { + float c = 0; + for (unsigned i = 0; i < n; ++i) + { + float v = vec[i]; + c += fabs (v); + } + return c; + } + + template <unsigned n, typename C> + float l1_distance(const C (&v1)[n], const C (&v2)[n]) + { + float d = 0; + for (unsigned i = 0; i < n; ++i) + { + float v = v1[i] - v2[i]; + d += fabs (v); + } + return d; + } + + template <unsigned n, typename C> + float l1(const metal::vec<n,C>& vec) + { + float c = 0; + for (unsigned i = 0; i < n; ++i) + if (vec[i] > 0) + c += vec[i]; + else + c -= vec[i]; + return c; + } + + template <unsigned n, typename C> + float l1(const metal::vec<n,C>& vec1, const metal::vec<n,C>& vec2) + { + float d = 0; + for (unsigned i = 0; i < n; ++i) + { + float v = vec1[i] - vec2[i]; + d += fabs (v); + } + return d; + } + +# endif // ! MLN_INCLUDE_ONLY + + } // end of namespace mln::norm + +} // end of namespace mln + + +#endif // ! MLN_NORM_L1_HH