[Olena-patches] 1415: Improve the L1-norm implementation.

https://svn.lrde.epita.fr/svn/oln/trunk/milena Index: ChangeLog from Roland Levillain &lt;roland(a)lrde.epita.fr&gt; Improve the L1-norm implementation. * mln/norm/l1.hh (mln::norm::l1_distance): Fix documentation. (mln::norm::l1_, mln::norm::l1_distance_): Avoid temporaries. l1.hh | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) Index: mln/norm/l1.hh --- mln/norm/l1.hh (revision 1415) +++ mln/norm/l1.hh (working copy) @@ -30,12 +30,13 @@ /*! \file mln/norm/l1.hh * - * \brief Define some l1-norm related routines. + * \brief Define some L1-norm related routines. * \see http://mathworld.wolfram.com/L1-Norm.html for more information. */ -# include <mln/metal/vec.hh> # include <mln/math/abs.hh> +# include <mln/metal/vec.hh> + namespace mln { @@ -52,7 +53,7 @@ mln_value_sum(C) l1(const metal::vec<n,C>& vec); /// \} - /// L1-norm distance between vectors \a v1 and \a v2. + /// L1-norm distance between vectors \a vec1 and \a vec2. /// \{ template <unsigned n, typename C> mln_value_sum(C) l1_distance(const C (&vec1)[n], const C (&vec2)[n]); @@ -68,33 +69,31 @@ namespace impl { template <unsigned n, typename C, typename V> - mln_value_sum(C) l1_(const V& vec) + mln_value_sum(C) + l1_(const V& vec) { - mln_value_sum(C) c = 0; + mln_value_sum(C) m = 0; for (unsigned i = 0; i < n; ++i) - { - mln_value_sum(C) v = vec[i]; - c += mln::math::abs (v); - } - return c; + m += mln::math::abs (vec[i]); + return m; } template <unsigned n, typename C, typename V> - mln_value_sum(C) l1_distance_(const V& vec1, const V& vec2) + mln_value_sum(C) + l1_distance_(const V& vec1, const V& vec2) { mln_value_sum(C) d = 0; for (unsigned i = 0; i < n; ++i) - { - mln_value_sum(C) v = vec1[i] - vec2[i]; - d += mln::math::abs (v); - } + d += mln::math::abs (vec1[i] - vec2[i]); return d; } } // end of namespace mln::norm::impl - // Facades. + /*----------. + | Facades. | + `----------*/ template <unsigned n, typename C> mln_value_sum(C)