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# Source code for astropy.cosmology._src.flrw.w0wacdm

    # Licensed under a 3-clause BSD style license - see LICENSE.rst
    # ruff: noqa: RUF009

    from numpy import exp

    from astropy.cosmology._src.core import dataclass_decorator
    from astropy.cosmology._src.parameter import Parameter
    from astropy.cosmology._src.utils import aszarr, deprecated_keywords

    from . import scalar_inv_efuncs
    from .base import FLRW, FlatFLRWMixin

    __all__ = ["Flatw0waCDM", "w0waCDM"]

    __doctest_requires__ = {"*": ["scipy"]}

    @dataclass_decorator
    class w0waCDM(FLRW):
        r"""FLRW cosmology with a CPL dark energy EoS and curvature.

        The equation for the dark energy equation of state (EoS) uses the
        CPL form as described in Chevallier & Polarski [1]_ and Linder [2]_:
        :math:`w(z) = w_0 + w_a (1-a) = w_0 + w_a z / (1+z)`.

        Parameters
        ----------
        H0 : float or scalar quantity-like ['frequency']
            Hubble constant at z = 0. If a float, must be in [km/sec/Mpc].

        Om0 : float
            Omega matter: density of non-relativistic matter in units of the
            critical density at z=0.

        Ode0 : float
            Omega dark energy: density of dark energy in units of the critical
            density at z=0.

        w0 : float, optional
            Dark energy equation of state at z=0 (a=1). This is pressure/density
            for dark energy in units where c=1.

        wa : float, optional
            Negative derivative of the dark energy equation of state with respect
            to the scale factor. A cosmological constant has w0=-1.0 and wa=0.0.

        Tcmb0 : float or scalar quantity-like ['temperature'], optional
            Temperature of the CMB z=0. If a float, must be in [K]. Default: 0 [K].
            Setting this to zero will turn off both photons and neutrinos
            (even massive ones).

        Neff : float, optional
            Effective number of Neutrino species. Default 3.04.

        m_nu : quantity-like ['energy', 'mass'] or array-like, optional
            Mass of each neutrino species in [eV] (mass-energy equivalency enabled).
            If this is a scalar Quantity, then all neutrino species are assumed to
            have that mass. Otherwise, the mass of each species. The actual number
            of neutrino species (and hence the number of elements of m_nu if it is
            not scalar) must be the floor of Neff. Typically this means you should
            provide three neutrino masses unless you are considering something like
            a sterile neutrino.

        Ob0 : float or None, optional
            Omega baryons: density of baryonic matter in units of the critical
            density at z=0.  If this is set to None (the default), any computation
            that requires its value will raise an exception.

        name : str or None (optional, keyword-only)
            Name for this cosmological object.

        meta : mapping or None (optional, keyword-only)
            Metadata for the cosmology, e.g., a reference.

        Examples
        --------
        >>> from astropy.cosmology import w0waCDM
        >>> cosmo = w0waCDM(H0=70, Om0=0.3, Ode0=0.7, w0=-0.9, wa=0.2)

        The comoving distance in Mpc at redshift z:

        >>> z = 0.5
        >>> dc = cosmo.comoving_distance(z)

        References
        ----------
        .. [1] Chevallier, M., & Polarski, D. (2001). Accelerating Universes with
               Scaling Dark Matter. International Journal of Modern Physics D,
               10(2), 213-223.
        .. [2] Linder, E. (2003). Exploring the Expansion History of the
               Universe. Phys. Rev. Lett., 90, 091301.
        """

        w0: Parameter = Parameter(
            default=-1.0, doc="Dark energy equation of state at z=0.", fvalidate="float"
        )
        wa: Parameter = Parameter(
            default=0.0,
            doc="Negative derivative of dark energy equation of state w.r.t. a.",
            fvalidate="float",
        )

        def __post_init__(self):
            super().__post_init__()

            # Please see :ref:`astropy-cosmology-fast-integrals` for discussion
            # about what is being done here.
            if self.Tcmb0.value == 0:
                inv_efunc_scalar = scalar_inv_efuncs.w0wacdm_inv_efunc_norel
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ok0,
                    self.w0,
                    self.wa,
                )
            elif not self._massivenu:
                inv_efunc_scalar = scalar_inv_efuncs.w0wacdm_inv_efunc_nomnu
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ok0,
                    self.Ogamma0 + self.Onu0,
                    self.w0,
                    self.wa,
                )
            else:
                inv_efunc_scalar = scalar_inv_efuncs.w0wacdm_inv_efunc
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ok0,
                    self.Ogamma0,
                    self._neff_per_nu,
                    self._nmasslessnu,
                    self._nu_y_list,
                    self.w0,
                    self.wa,
                )
            object.__setattr__(self, "_inv_efunc_scalar", inv_efunc_scalar)
            object.__setattr__(self, "_inv_efunc_scalar_args", inv_efunc_scalar_args)

        @deprecated_keywords("z", since="7.0")
        def w(self, z):
            r"""Returns dark energy equation of state at redshift ``z``.

            Parameters
            ----------
            z : Quantity-like ['redshift'] or array-like
                Input redshift.

                .. versionchanged:: 7.0
                    Passing z as a keyword argument is deprecated.

            Returns
            -------
            w : ndarray or float
                The dark energy equation of state
                Returns `float` if the input is scalar.

            Notes
            -----
            The dark energy equation of state is defined as
            :math:`w(z) = P(z)/\rho(z)`, where :math:`P(z)` is the pressure at
            redshift z and :math:`\rho(z)` is the density at redshift z, both in
            units where c=1. Here this is
            :math:`w(z) = w_0 + w_a (1 - a) = w_0 + w_a \frac{z}{1+z}`.
            """
            z = aszarr(z)
            return self.w0 + self.wa * z / (z + 1.0)

        @deprecated_keywords("z", since="7.0")
        def de_density_scale(self, z):
            r"""Evaluates the redshift dependence of the dark energy density.

            Parameters
            ----------
            z : Quantity-like ['redshift'] or array-like, positional-only
                Input redshift.

                .. versionchanged:: 7.0
                    Passing z as a keyword argument is deprecated.

            Returns
            -------
            I : ndarray or float
                The scaling of the energy density of dark energy with redshift.
                Returns `float` if the input is scalar.

            Notes
            -----
            The scaling factor, I, is defined by :math:`\rho(z) = \rho_0 I`,
            and in this case is given by

            .. math::

               I = \left(1 + z\right)^{3 \left(1 + w_0 + w_a\right)}
                         \exp \left(-3 w_a \frac{z}{1+z}\right)
            """
            z = aszarr(z)
            zp1 = z + 1.0  # (converts z [unit] -> z [dimensionless])
            return zp1 ** (3 * (1 + self.w0 + self.wa)) * exp(-3 * self.wa * z / zp1)

    @dataclass_decorator
    class Flatw0waCDM(FlatFLRWMixin, w0waCDM):
        """FLRW cosmology with a CPL dark energy EoS and no curvature.

        The equation for the dark energy equation of state (EoS) uses the CPL form as
        described in Chevallier & Polarski [1]_ and Linder [2]_:
        :math:`w(z) = w_0 + w_a (1-a) = w_0 + w_a z / (1+z)`.

        Parameters
        ----------
        H0 : float or scalar quantity-like ['frequency']
            Hubble constant at z = 0. If a float, must be in [km/sec/Mpc].

        Om0 : float
            Omega matter: density of non-relativistic matter in units of the
            critical density at z=0.

        w0 : float, optional
            Dark energy equation of state at z=0 (a=1). This is pressure/density
            for dark energy in units where c=1.

        wa : float, optional
            Negative derivative of the dark energy equation of state with respect
            to the scale factor. A cosmological constant has w0=-1.0 and wa=0.0.

        Tcmb0 : float or scalar quantity-like ['temperature'], optional
            Temperature of the CMB z=0. If a float, must be in [K]. Default: 0 [K].
            Setting this to zero will turn off both photons and neutrinos
            (even massive ones).

        Neff : float, optional
            Effective number of Neutrino species. Default 3.04.

        m_nu : quantity-like ['energy', 'mass'] or array-like, optional
            Mass of each neutrino species in [eV] (mass-energy equivalency enabled).
            If this is a scalar Quantity, then all neutrino species are assumed to
            have that mass. Otherwise, the mass of each species. The actual number
            of neutrino species (and hence the number of elements of m_nu if it is
            not scalar) must be the floor of Neff. Typically this means you should
            provide three neutrino masses unless you are considering something like
            a sterile neutrino.

        Ob0 : float or None, optional
            Omega baryons: density of baryonic matter in units of the critical
            density at z=0.  If this is set to None (the default), any computation
            that requires its value will raise an exception.

        name : str or None (optional, keyword-only)
            Name for this cosmological object.

        meta : mapping or None (optional, keyword-only)
            Metadata for the cosmology, e.g., a reference.

        Examples
        --------
        >>> from astropy.cosmology import Flatw0waCDM
        >>> cosmo = Flatw0waCDM(H0=70, Om0=0.3, w0=-0.9, wa=0.2)

        The comoving distance in Mpc at redshift z:

        >>> z = 0.5
        >>> dc = cosmo.comoving_distance(z)

        To get an equivalent cosmology, but of type `astropy.cosmology.w0waCDM`,
        use :attr:`astropy.cosmology.FlatFLRWMixin.nonflat`.

        >>> print(cosmo.nonflat)
        w0waCDM(H0=70.0 km / (Mpc s), Om0=0.3, Ode0=0.7, ...

        References
        ----------
        .. [1] Chevallier, M., & Polarski, D. (2001). Accelerating Universes with
               Scaling Dark Matter. International Journal of Modern Physics D,
               10(2), 213-223.
        .. [2] Linder, E. (2003). Exploring the Expansion History of the
               Universe. Phys. Rev. Lett., 90, 091301.
        """

        def __post_init__(self):
            super().__post_init__()

            # Please see :ref:`astropy-cosmology-fast-integrals` for discussion
            # about what is being done here.
            if self.Tcmb0.value == 0:
                inv_efunc_scalar = scalar_inv_efuncs.fw0wacdm_inv_efunc_norel
                inv_efunc_scalar_args = (self.Om0, self.Ode0, self.w0, self.wa)
            elif not self._massivenu:
                inv_efunc_scalar = scalar_inv_efuncs.fw0wacdm_inv_efunc_nomnu
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ogamma0 + self.Onu0,
                    self.w0,
                    self.wa,
                )
            else:
                inv_efunc_scalar = scalar_inv_efuncs.fw0wacdm_inv_efunc
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ogamma0,
                    self._neff_per_nu,
                    self._nmasslessnu,
                    self._nu_y_list,
                    self.w0,
                    self.wa,
                )
            object.__setattr__(self, "_inv_efunc_scalar", inv_efunc_scalar)
            object.__setattr__(self, "_inv_efunc_scalar_args", inv_efunc_scalar_args)