Source code for blackjax.types
# Copyright 2020- The Blackjax Authors.
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from typing import Any, Iterable, Mapping, Union
import jax
from jax.typing import ArrayLike
"""
Following the current best practice (https://jax.readthedocs.io/en/latest/jax.typing.html)
We use:
- `ArrayLike` and `ArrayLikeTree` to annotate function input,
- `Array` and `ArrayTree` to annotate function output.
Leaves of a Pytree definition in the library are in principle annotated as
`Array`, as they are mostly internal representation. For example:
```
class WelfordAlgorithmState(NamedTuple):
mean: Array
...
```
[TODO] Improve scalar-like typing (e.g. `logdensity`, `acceptance_rate`).
While they are `Array` (as in most cases they should be output of a Jax
function), we annotate them as `float` to empathizes they should be scalar
(until we introduce shape annotation).
"""
#: JAX PyTrees
[docs]
ArrayTree = Union[jax.Array, Iterable["ArrayTree"], Mapping[Any, "ArrayTree"]]
[docs]
ArrayLikeTree = Union[
ArrayLike, Iterable["ArrayLikeTree"], Mapping[Any, "ArrayLikeTree"]
]
#: JAX PRNGKey
