blob: f613ced3542243f28930a8e2c44c326674d7481c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
|
// Copyright 2019 Hans Dembinski
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt
// or copy at http://www.boost.org/LICENSE_1_0.txt)
#include <array>
#include <random>
using uniform = std::uniform_real_distribution<>;
using uniform_int = std::uniform_int_distribution<>;
using normal = std::normal_distribution<>;
template <class Distribution, class... Ts>
Distribution init(Ts...);
template <>
uniform init<uniform>() {
return uniform{0.0, 1.0};
}
template <>
normal init<normal>() {
return normal{0.5, 0.3};
}
template <>
uniform_int init<uniform_int, int>(int n) {
return uniform_int{0, n};
}
template <class Distribution, std::size_t N = 1 << 15>
struct generator : std::array<double, N> {
using base_t = std::array<double, N>;
template <class... Ts>
generator(Ts... ts) {
std::default_random_engine rng(1);
auto dis = init<Distribution>(ts...);
std::generate(base_t::begin(), base_t::end(), [&] { return dis(rng); });
}
const double& operator()() {
++ptr_;
if (ptr_ == base_t::data() + N) ptr_ = base_t::data();
return *ptr_;
}
const double* ptr_ = base_t::data() - 1;
};
|
