mpi2

iterators.hh
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			/**
			* @file aka_iterators.hh
			*
			* @author Nicolas Richart
			*
			* @date creation Wed Jul 19 2017
			*
			* @brief iterator interfaces
			*
			* @section LICENSE
			*
			* Copyright (©) 2010-2011 EPFL (Ecole Polytechnique Fédérale de Lausanne)
			* Laboratory (LSMS - Laboratoire de Simulation en Mécanique des Solides)
			*
			* Akantu is free software: you can redistribute it and/or modify it under the
			* terms of the GNU Lesser General Public License as published by the Free
			* Software Foundation, either version 3 of the License, or (at your option) any
			* later version.
			*
			* Akantu 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 Lesser General Public License for more
			* details.
			*
			* You should have received a copy of the GNU Lesser General Public License
			* along with Akantu. If not, see <http://www.gnu.org/licenses/>.
			*
			* Above block was left intact as in akantu. µSpectre exercises the
			* right to redistribute and modify the code below
			*
			*/
			/* -------------------------------------------------------------------------- */
			#include <tuple>
			#include <utility>
			/* -------------------------------------------------------------------------- */

			#ifndef __AKANTU_AKA_ITERATORS_HH__
			#define __AKANTU_AKA_ITERATORS_HH__

			namespace akantu {

			namespace tuple {
			/* ------------------------------------------------------------------------ */
			namespace details {
			template <size_t N> struct Foreach {
			template <class Tuple>
			static inline bool not_equal(Tuple && a, Tuple && b) {
			if (std::get<N - 1>(std::forward<Tuple>(a)) ==
			std::get<N - 1>(std::forward<Tuple>(b)))
			return false;
			return Foreach<N - 1>::not_equal(std::forward<Tuple>(a),
			std::forward<Tuple>(b));
			}
			};

			/* ---------------------------------------------------------------------- */
			template <> struct Foreach<0> {
			template <class Tuple>
			static inline bool not_equal(Tuple && a, Tuple && b) {
			return std::get<0>(std::forward<Tuple>(a)) !=
			std::get<0>(std::forward<Tuple>(b));
			}
			};

			template <typename... Ts>
			decltype(auto) make_tuple_no_decay(Ts &&... args) {
			return std::tuple<Ts...>(std::forward<Ts>(args)...);
			}

			template <class F, class Tuple, size_t... Is>
			void foreach_impl(F && func, Tuple && tuple,
			std::index_sequence<Is...> &&) {
			(void)std::initializer_list<int>{
			(std::forward<F>(func)(std::get<Is>(std::forward<Tuple>(tuple))),
			0)...};
			}

			template <class F, class Tuple, size_t... Is>
			decltype(auto) transform_impl(F && func, Tuple && tuple,
			std::index_sequence<Is...> &&) {
			return make_tuple_no_decay(
			std::forward<F>(func)(std::get<Is>(std::forward<Tuple>(tuple)))...);
			}
			}; // namespace details

			/* ------------------------------------------------------------------------ */
			template <class Tuple> bool are_not_equal(Tuple && a, Tuple && b) {
			return details::Foreach<std::tuple_size<std::decay_t<Tuple>>::value>::
			not_equal(std::forward<Tuple>(a), std::forward<Tuple>(b));
			}

			template <class F, class Tuple> void foreach (F && func, Tuple && tuple) {
			return details::foreach_impl(
			std::forward<F>(func), std::forward<Tuple>(tuple),
			std::make_index_sequence<
			std::tuple_size<std::decay_t<Tuple>>::value>{});
			}

			template <class F, class Tuple>
			decltype(auto) transform(F && func, Tuple && tuple) {
			return details::transform_impl(
			std::forward<F>(func), std::forward<Tuple>(tuple),
			std::make_index_sequence<
			std::tuple_size<std::decay_t<Tuple>>::value>{});
			}
			} // namespace tuple

			/* -------------------------------------------------------------------------- */
			namespace iterators {
			template <class... Iterators> class ZipIterator {
			private:
			using tuple_t = std::tuple<Iterators...>;

			public:
			explicit ZipIterator(tuple_t iterators) : iterators(std::move(iterators)) {}

			decltype(auto) operator*() {
			return tuple::transform([] (auto && it) -> decltype(auto) {return *it;}, iterators);
			}

			ZipIterator & operator++() {
			tuple::foreach ([] (auto && it) { ++it; }, iterators);
			return *this;
			}

			bool operator==(const ZipIterator & other) const {
			return not tuple::are_not_equal(iterators, other.iterators);
			}

			bool operator!=(const ZipIterator & other) const {
			return tuple::are_not_equal(iterators, other.iterators);
			}

			private:
			tuple_t iterators;
			};
			} // namespace iterators

			/* -------------------------------------------------------------------------- */
			template <class... Iterators>
			decltype(auto) zip_iterator(std::tuple<Iterators...> && iterators_tuple) {
			auto zip = iterators::ZipIterator<Iterators...>(
			std::forward<decltype(iterators_tuple)>(iterators_tuple));
			return zip;
			}

			/* -------------------------------------------------------------------------- */
			namespace containers {
			template <class... Containers> class ZipContainer {
			using containers_t = std::tuple<Containers...>;

			public:
			explicit ZipContainer(Containers &&... containers)
			: containers(std::forward<Containers>(containers)...) {}

			decltype(auto) begin() const {
			return zip_iterator(
			tuple::transform([] (auto && c) { return c.begin(); },
			std::forward<containers_t>(containers)));
			}

			decltype(auto) end() const {
			return zip_iterator(
			tuple::transform([] (auto && c) { return c.end(); },
			std::forward<containers_t>(containers)));
			}

			decltype(auto) begin() {
			return zip_iterator(
			tuple::transform([] (auto && c) { return c.begin(); },
			std::forward<containers_t>(containers)));
			}

			decltype(auto) end() {
			return zip_iterator(
			tuple::transform([] (auto && c) { return c.end(); },
			std::forward<containers_t>(containers)));
			}

			private:
			containers_t containers;
			};
			} // namespace containers

			/* -------------------------------------------------------------------------- */
			template <class... Containers> decltype(auto) zip(Containers &&... conts) {
			return containers::ZipContainer<Containers...>(
			std::forward<Containers>(conts)...);
			}

			/* -------------------------------------------------------------------------- */
			/* Arange */
			/* -------------------------------------------------------------------------- */
			namespace iterators {
			template <class T> class ArangeIterator {
			public:
			using value_type = T;
			using pointer = T *;
			using reference = T &;
			using iterator_category = std::input_iterator_tag;

			constexpr ArangeIterator(T value, T step) : value(value), step(step) {}
			constexpr ArangeIterator(const ArangeIterator &) = default;

			constexpr ArangeIterator & operator++() {
			value += step;
			return *this;
			}

			constexpr const T & operator*() const { return value; }

			constexpr bool operator==(const ArangeIterator & other) const {
			return (value == other.value) and (step == other.step);
			}

			constexpr bool operator!=(const ArangeIterator & other) const {
			return not operator==(other);
			}

			private:
			T value{0};
			const T step{1};
			};
			} // namespace iterators

			namespace containers {
			template <class T> class ArangeContainer {
			public:
			using iterator = iterators::ArangeIterator<T>;

			constexpr ArangeContainer(T start, T stop, T step = 1)
			: start(start), stop((stop - start) % step == 0
			? stop
			: start + (1 + (stop - start) / step) * step),
			step(step) {}
			explicit constexpr ArangeContainer(T stop) : ArangeContainer(0, stop, 1) {}

			constexpr T operator[](size_t i) {
			T val = start + i * step;
			assert(val < stop && "i is out of range");
			return val;
			}

			constexpr T size() { return (stop - start) / step; }

			constexpr iterator begin() { return iterator(start, step); }
			constexpr iterator end() { return iterator(stop, step); }

			private:
			const T start{0}, stop{0}, step{1};
			};
			} // namespace containers

			template <class T,
			typename = std::enable_if_t<std::is_integral<std::decay_t<T>>::value>>
			inline decltype(auto) arange(const T & stop) {
			return containers::ArangeContainer<T>(stop);
			}

			template <class T1, class T2,
			typename = std::enable_if_t<
			std::is_integral<std::common_type_t<T1, T2>>::value>>
			inline constexpr decltype(auto) arange(const T1 & start, const T2 & stop) {
			return containers::ArangeContainer<std::common_type_t<T1, T2>>(start, stop);
			}

			template <class T1, class T2, class T3,
			typename = std::enable_if_t<
			std::is_integral<std::common_type_t<T1, T2, T3>>::value>>
			inline constexpr decltype(auto) arange(const T1 & start, const T2 & stop,
			const T3 & step) {
			return containers::ArangeContainer<std::common_type_t<T1, T2, T3>>(
			start, stop, step);
			}

			/* -------------------------------------------------------------------------- */

			template <class Container>
			inline constexpr decltype(auto) enumerate(Container && container,
			size_t start_ = 0) {
			auto stop = std::forward<Container>(container).size();
			decltype(stop) start = start_;
			return zip(arange(start, stop), std::forward<Container>(container));
			}

			} // namespace akantu

			#endif /* __AKANTU_AKA_ITERATORS_HH__ */

muSpectre/src/common/iterators.hh84a3bfa99993feat/mpi2

iterators.hhView Options

muSpectre/src/common/iterators.hh
84a3bfa99993feat/mpi2

iterators.hh
View Options