Source code for xformers.components.positional_embedding
# Copyright (c) Facebook, Inc. and its affiliates. All rights reserved.
#
# This source code is licensed under the BSD license found in the
# LICENSE file in the root directory of this source tree.
from pathlib import Path
from typing import Any, Callable, Dict, Set, Union
from xformers.utils import (
generate_matching_config,
get_registry_decorator,
import_all_modules,
)
from .base import PositionEmbedding, PositionEmbeddingConfig # noqa
# CREDITS: Classy Vision registry mechanism
POSITION_EMBEDDING_REGISTRY: Dict[str, Any] = {}
POSITION_EMBEDDING_CLASS_NAMES: Set[str] = set()
[docs]def build_positional_embedding(config: Union[Dict[str, Any], PositionEmbeddingConfig]):
"""Builds a position encoding from a config.
This assumes a 'name' key in the config which is used to determine what
attention class to instantiate. For instance, a config `{"name": "my_position_encoding",
"foo": "bar"}` will find a class that was registered as "my_position_encoding"
(see :func:`register_positional_embedding`) and call .from_config on it."""
if not isinstance(config, PositionEmbeddingConfig):
config_instance = generate_matching_config(
config, POSITION_EMBEDDING_REGISTRY[config["name"]].config
)
else:
config_instance = config
return POSITION_EMBEDDING_REGISTRY[config_instance.name].constructor.from_config(
config_instance
)
"""Registers a PositionEncoding subclass.
This decorator allows xFormers to instantiate a subclass of PositionEncoding
from a configuration file, even if the class itself is not part of the
xFormers framework. To use it, apply this decorator to a `PositionEncoding`
subclass, like this:
.. code-block:: python
@dataclass
class MyConfig:
...
@register_positional_embedding('my_encoding', MyConfig)
class MyEncoding(PositionEncoding):
...
To instantiate a position encoding from a configuration file, see :func:`build_positional_embedding`."""
register_positional_embedding: Callable[
[str, Any], Callable[[Any], Any]
] = get_registry_decorator(
POSITION_EMBEDDING_REGISTRY,
POSITION_EMBEDDING_CLASS_NAMES,
PositionEmbedding,
PositionEmbeddingConfig,
)
from .rotary import RotaryEmbedding # noqa
from .sine import SinePositionalEmbedding # type: ignore # noqa
from .vocab import VocabEmbedding # noqa
__all__ = [
"RotaryEmbedding",
"SinePositionalEmbedding",
"VocabEmbedding",
"build_positional_embedding",
"register_positional_embedding",
]
# automatically import any Python files in the directory
import_all_modules(
str(Path(__file__).parent), "xformers.components.positional_embedding"
)