Source code for pyro.poutine.mask_messenger

# Copyright (c) 2017-2019 Uber Technologies, Inc.
# SPDX-License-Identifier: Apache-2.0

from typing import TYPE_CHECKING, Union

import torch

from pyro.poutine.messenger import Messenger

if TYPE_CHECKING:
    from pyro.poutine.runtime import Message


[docs]class MaskMessenger(Messenger): """ Given a stochastic function with some batched sample statements and masking tensor, mask out some of the sample statements elementwise. :param fn: a stochastic function (callable containing Pyro primitive calls) :param torch.BoolTensor mask: a ``{0,1}``-valued masking tensor (1 includes a site, 0 excludes a site) :returns: stochastic function decorated with a :class:`~pyro.poutine.scale_messenger.MaskMessenger` """ def __init__(self, mask: Union[bool, torch.BoolTensor]) -> None: if isinstance(mask, torch.Tensor): if mask.dtype != torch.bool: raise ValueError( "Expected mask to be a BoolTensor but got {}".format(type(mask)) ) elif mask not in (True, False): raise ValueError( "Expected mask to be a boolean but got {}".format(type(mask)) ) super().__init__() self.mask = mask def _process_message(self, msg: "Message") -> None: msg["mask"] = self.mask if msg["mask"] is None else msg["mask"] & self.mask