Source code for lightning.pytorch.utilities.seed

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#     http://www.apache.org/licenses/LICENSE-2.0
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"""Utilities to help with reproducibility of models."""

from contextlib import contextmanager
from typing import Generator

from lightning.fabric.utilities.seed import _collect_rng_states, _set_rng_states


[docs]@contextmanager def isolate_rng(include_cuda: bool = True) -> Generator[None, None, None]: """A context manager that resets the global random state on exit to what it was before entering. It supports isolating the states for PyTorch, Numpy, and Python built-in random number generators. Args: include_cuda: Whether to allow this function to also control the `torch.cuda` random number generator. Set this to ``False`` when using the function in a forked process where CUDA re-initialization is prohibited. Example: >>> import torch >>> torch.manual_seed(1) # doctest: +ELLIPSIS <torch._C.Generator object at ...> >>> with isolate_rng(): ... [torch.rand(1) for _ in range(3)] [tensor([0.7576]), tensor([0.2793]), tensor([0.4031])] >>> torch.rand(1) tensor([0.7576]) """ states = _collect_rng_states(include_cuda) yield _set_rng_states(states)