# mypy: disable-error-code="operator,union-attr"
from typing import Optional, Union, Annotated
from caskade import forward, Param
from .base import Source, NameType
from . import func
from ..backend_obj import ArrayLike
__all__ = ("StarSource",)
[docs]
class StarSource(Source):
"""
`Star` is a subclass of the abstract class `Source`.
It represents a star source in a gravitational lensing system.
The Star profile is meant to describe individual light sources.
Attributes
-----------
x0: Optional[ArrayLike]
The x-coordinate of the Star source's center.
*Unit: arcsec*
y0: Optional[ArrayLike]
The y-coordinate of the Star source's center.
*Unit: arcsec*
theta_s: Optional[ArrayLike]
The radius of the star.
*Unit: arcsec*
Ie: Optional[ArrayLike]
The intensity at the center of the star.
*Unit: flux*
gamma: Optional[ArrayLike]
The linear limb darkening coefficient.
*Unit: unitless*
"""
def __init__(
self,
x0: Annotated[
Optional[Union[ArrayLike, float]],
"The x-coordinate of the star source's center",
True,
] = None,
y0: Annotated[
Optional[Union[ArrayLike, float]],
"The y-coordinate of the star source's center",
True,
] = None,
theta_s: Annotated[
Optional[Union[ArrayLike, float]],
"The radius of the star source",
True,
] = None,
Ie: Annotated[
Optional[Union[ArrayLike, float]],
"The intensity at the effective radius",
True,
] = None,
gamma: Annotated[
Optional[Union[ArrayLike, float]],
"The linear limb darkening coefficient",
True,
] = None,
name: NameType = None,
):
"""
Constructs the `Star` object with the given parameters.
Parameters
----------
name: str
The name of the source.
x0: Optional[ArrayLike]
The x-coordinate of the star source's center.
*Unit: arcsec*
y0: Optional[ArrayLike]
The y-coordinate of the star source's center.
*Unit: arcsec*
theta_s: Optional[ArrayLike]
The radius of the star.
*Unit: arcsec*
Ie: Optional[ArrayLike]
The intensity at the center of the source.
*Unit: flux*
gamma: Optional[ArrayLike]
The linear limb darkening coefficient.
*Unit: unitless*
"""
super().__init__(name=name)
self.x0 = Param("x0", x0, shape=(), units="arcsec")
self.y0 = Param("y0", y0, shape=(), units="arcsec")
self.theta_s = Param(
"theta_s", theta_s, shape=(), units="arcsec", valid=(0, None)
)
self.Ie = Param("Ie", Ie, shape=(), units="flux", valid=(0, None))
self.gamma = Param("gamma", gamma, shape=(), units="unitless", valid=(0, 1))
[docs]
@forward
def brightness(
self,
x,
y,
x0: Annotated[ArrayLike, "Param"],
y0: Annotated[ArrayLike, "Param"],
theta_s: Annotated[ArrayLike, "Param"],
Ie: Annotated[ArrayLike, "Param"],
gamma: Annotated[ArrayLike, "Param"],
):
"""
Implements the `brightness` method for `star`. This method calculates the
brightness of the source at the given point(s).
Parameters
----------
x: ArrayLike
The x-coordinate(s) at which to calculate the source brightness.
This could be a single value or a tensor of values.
*Unit: arcsec*
y: ArrayLike
The y-coordinate(s) at which to calculate the source brightness.
This could be a single value or a tensor of values.
*Unit: arcsec*
Returns
-------
ArrayLike
The brightness of the source at the given point(s).
The output tensor has the same shape as `x` and `y`.
*Unit: flux*
"""
return func.brightness_star(x0, y0, theta_s, Ie, x, y, gamma)
