Source code for gymnasium.utils.seeding
"""Set of random number generator functions: seeding, generator, hashing seeds."""
from typing import Any, Optional, Tuple
import numpy as np
from gymnasium import error
[docs]def np_random(seed: Optional[int] = None) -> Tuple[np.random.Generator, Any]:
"""Generates a random number generator from the seed and returns the Generator and seed.
Args:
seed: The seed used to create the generator
Returns:
The generator and resulting seed
Raises:
Error: Seed must be a non-negative integer or omitted
"""
if seed is not None and not (isinstance(seed, int) and 0 <= seed):
if isinstance(seed, int) is False:
raise error.Error(
f"Seed must be a python integer, actual type: {type(seed)}"
)
else:
raise error.Error(
f"Seed must be greater or equal to zero, actual value: {seed}"
)
seed_seq = np.random.SeedSequence(seed)
np_seed = seed_seq.entropy
rng = RandomNumberGenerator(np.random.PCG64(seed_seq))
return rng, np_seed
RNG = RandomNumberGenerator = np.random.Generator