016532f011
huge refactor, various speed improvements, potential for further improvements and parallelization
51 lines
1.2 KiB
C++
51 lines
1.2 KiB
C++
// Copyright 2019 Hans Dembinski
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//
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// Distributed under the Boost Software License, Version 1.0.
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// (See accompanying file LICENSE_1_0.txt
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// or copy at http://www.boost.org/LICENSE_1_0.txt)
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#include <array>
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#include <random>
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using uniform = std::uniform_real_distribution<>;
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using uniform_int = std::uniform_int_distribution<>;
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using normal = std::normal_distribution<>;
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template <class Distribution, class... Ts>
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Distribution init(Ts...);
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template <>
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uniform init<uniform>() {
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return uniform{0.0, 1.0};
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}
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template <>
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normal init<normal>() {
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return normal{0.5, 0.3};
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}
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template <>
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uniform_int init<uniform_int, int>(int n) {
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return uniform_int{0, n};
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}
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template <class Distribution, std::size_t N = 1 << 15>
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struct generator : std::array<double, N> {
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using base_t = std::array<double, N>;
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template <class... Ts>
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generator(Ts... ts) {
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std::default_random_engine rng(1);
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auto dis = init<Distribution>(ts...);
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std::generate(base_t::begin(), base_t::end(), [&] { return dis(rng); });
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}
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const double& operator()() {
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++ptr_;
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if (ptr_ == base_t::data() + N) ptr_ = base_t::data();
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return *ptr_;
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}
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const double* ptr_ = base_t::data() - 1;
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};
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