diff options
Diffstat (limited to 'src/boost/libs/hana/example/cppcon_2014/matrix/ring.hpp')
-rw-r--r-- | src/boost/libs/hana/example/cppcon_2014/matrix/ring.hpp | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/src/boost/libs/hana/example/cppcon_2014/matrix/ring.hpp b/src/boost/libs/hana/example/cppcon_2014/matrix/ring.hpp new file mode 100644 index 000000000..748f4f8a3 --- /dev/null +++ b/src/boost/libs/hana/example/cppcon_2014/matrix/ring.hpp @@ -0,0 +1,62 @@ +// Copyright Louis Dionne 2013-2017 +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) + +#ifndef BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_RING_HPP +#define BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_RING_HPP + +#include "matrix.hpp" + +#include <boost/hana/equal.hpp> +#include <boost/hana/fwd/mult.hpp> +#include <boost/hana/fwd/one.hpp> +#include <boost/hana/if.hpp> +#include <boost/hana/integral_constant.hpp> +#include <boost/hana/range.hpp> +#include <boost/hana/replicate.hpp> +#include <boost/hana/transform.hpp> +#include <boost/hana/tuple.hpp> +#include <boost/hana/unpack.hpp> +#include <boost/hana/zip_with.hpp> + +#include <utility> + + +namespace boost { namespace hana { + template <unsigned R1, unsigned C1, unsigned R2, unsigned C2> + struct mult_impl<cppcon::Matrix<R1, C1>, cppcon::Matrix<R2, C2>> { + template <typename M1, typename M2> + static constexpr decltype(auto) apply(M1&& m1, M2&& m2) { + static_assert(C1 == R2, + "wrong dimensions for matrix multiplication"); + auto cols = cppcon::columns(std::forward<M2>(m2)); + return unpack( + transform(cppcon::rows(std::forward<M1>(m1)), + [&](auto&& row) -> decltype(auto) { + return zip_with(cppcon::detail::tuple_scalar_product, + replicate<tuple_tag>(std::forward<decltype(row)>(row), uint_c<R1>), + cols + ); + } + ), + cppcon::matrix + ); + } + }; + + template <unsigned R, unsigned C> + struct one_impl<cppcon::Matrix<R, C>> { + static constexpr decltype(auto) apply() { + return unpack(range_c<unsigned, 0, R>, [](auto ...n) { + return unpack(range_c<unsigned, 0, C>, [=](auto ...m) { + auto row = [=](auto n) { + return cppcon::row(if_(n == m, int_c<1>, int_c<0>)...); + }; + return cppcon::matrix(row(n)...); + }); + }); + } + }; +}} + +#endif // !BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_RING_HPP |