Source code for astropy.cosmology._src.traits.darkmatter
__all__ = ["DarkMatterComponent"]
from collections.abc import Callable
from typing import Any
from numpy.typing import ArrayLike, NDArray
from astropy.cosmology._src.typing import FArray
from astropy.cosmology._src.utils import aszarr, deprecated_keywords
from astropy.units import Quantity
[docs]
class DarkMatterComponent:
"""The cosmology has attributes and methods for the dark matter density.
This trait provides an ``Odm`` method that returns the dark matter
density parameter (i.e., total matter minus baryons) at redshift ``z``.
"""
Odm0: float
"""Omega dark matter: dark matter density/critical density at z=0."""
inv_efunc: Callable[[NDArray[Any]], NDArray[Any]]
[docs]
@deprecated_keywords("z", since="7.0")
def Odm(self, z: Quantity | ArrayLike) -> FArray:
"""Return the density parameter for dark matter at redshift ``z``.
Parameters
----------
z : Quantity-like ['redshift'], array-like
Input redshift.
.. versionchanged:: 7.0
Passing z as a keyword argument is deprecated.
Returns
-------
Odm : ndarray
The density of dark matter relative to the critical density at
each redshift.
"""
z = aszarr(z)
return self.Odm0 * (z + 1.0) ** 3 * self.inv_efunc(z) ** 2