Param

class pmrf.parameters.Param(*, value: ArrayLike | None = None, distribution: AbstractDistribution | None = None, constraint: AbstractConstraint | None = None, name: str | None = None, scale: Any = 1.0, fixed: bool = False, metadata: Any = None, raw_value: Any = None)

Bases: AbstractVariable, AbstractWrappable[Array], AbstractAnnotated[Any]

The canonical parameter container for ParamRF.

Parameters can be created by instantiating this class, or using factories in pmrf.parameters, most of which are re-exported at root (e.g. pmrf.Unconstrained(), pmrf.Fixed(), pmrf.Bounded()).

Wraps a Parax variable, applying an optional scale, name and metadata.

Creates a generic parameter.

The incoming value can be any ArrayLike object.

Parameters:

value (ArrayLike, optional) – The unscaled value of the parameter.
distribution (Optional[AbstractDistribution], optional) – The unscaled probability distribution for the parameter. See pmrf.distributions.
constraint (Optional[AbstractConstraint], optional) – The unscaled constraint to apply to the parameter. See pmrf.constraints.
name (str, optional) – A name for the parameter, by default None.
scale (float, optional) – The scaling factor to apply, by default 1.0.
fixed (bool, optional) – Initializes the parameter as fixed. Defaults to False.
metadata (Any, optional) – Arbitrary metadata for the parameter, by default None.
raw_value (Optional[prx.AbstractVariable], optional) – The raw Parax variable to wrap. Mutually exclusive with value.

as_fixed() → Param

Returns a fixed version of this parameter.

Returns:: A new parameter instance wrapped as fixed.
Return type:: Param

as_free() → Param

Returns a free (variable) version of this parameter.

Returns:: A new parameter instance wrapped as free.
Return type:: Param

at(where: Callable[[Self], T] | str | tuple[str, ...] | list[str]) → Lens[Self, T]

(experimental) A functional interface for parameter manipulation.

This is a wrapper around equinox.tree_at via the jax-optix library.

Similar to pmrf.Model.at() but only accepts callables. See the documentation for that method for more details.

Returns:: A lens object focused on the root of the current instance.
Return type:: Lens

wrap(value: Array) → Self

Updates the internal state of the parameter using a physical value.

Parameters:: value (Array) – The physical value to wrap.
Returns:: A new instance of the parameter with the updated state.
Return type:: Self
Raises:: ValueError – If the underlying Parax variable is not wrappable.

The unscaled lower and upper bounds of the parameter.

Returns:: A tuple of (lower_bound, upper_bound) if bounds exist, otherwise None.
Return type:: tuple[ArrayLike, ArrayLike] | None

property constraint: AbstractConstraint | None

The unscaled constraint associated with the parameter.

Returns:: The constraint if one exists, otherwise None.
Return type:: AbstractConstraint | None

property distribution: AbstractDistribution | None

The unscaled probability distribution associated with the parameter.

Returns:: The distribution if one exists, otherwise None.
Return type:: AbstractDistribution | None

property fixed: bool

Indicates whether the parameter is fixed (constant).

Returns:: True if the parameter is fixed, False otherwise.
Return type:: bool

metadata: Any = None: Arbitrary metadata to store alongside the parameter.

name: str | None = None: A name for the parameter.

raw_value: AbstractVariable: The raw value of the parameter.

scale: float = 1.0: The scale of the parameter.

property unscaled_value: Array

Returns the original unscaled value.

Returns:: The computed array value.
Return type:: jax.Array

property value: Array

Returns the scaled physical value.

Returns:: The computed array value.
Return type:: jax.Array