1 | #include "duckdb/common/random_engine.hpp" |
---|---|
2 | #include "pcg_random.hpp" |
3 | #include <random> |
4 | |
5 | namespace duckdb { |
6 | |
7 | struct RandomState { |
8 | RandomState() { |
9 | } |
10 | |
11 | pcg32 pcg; |
12 | }; |
13 | |
14 | RandomEngine::RandomEngine(int64_t seed) : random_state(make_uniq<RandomState>()) { |
15 | if (seed < 0) { |
16 | random_state->pcg.seed(args: pcg_extras::seed_seq_from<std::random_device>()); |
17 | } else { |
18 | random_state->pcg.seed(args&: seed); |
19 | } |
20 | } |
21 | |
22 | RandomEngine::~RandomEngine() { |
23 | } |
24 | |
25 | double RandomEngine::NextRandom(double min, double max) { |
26 | D_ASSERT(max >= min); |
27 | return min + (NextRandom() * (max - min)); |
28 | } |
29 | |
30 | double RandomEngine::NextRandom() { |
31 | return std::ldexp(x: random_state->pcg(), exp: -32); |
32 | } |
33 | uint32_t RandomEngine::NextRandomInteger() { |
34 | return random_state->pcg(); |
35 | } |
36 | |
37 | void RandomEngine::SetSeed(uint32_t seed) { |
38 | random_state->pcg.seed(args&: seed); |
39 | } |
40 | |
41 | } // namespace duckdb |
42 |