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# Source code for astropy.cosmology._src.flrw.w0wzcdm

    # Licensed under a 3-clause BSD style license - see LICENSE.rst

    __all__ = ("Flatw0wzCDM", "w0wzCDM")

    from numpy import exp
    from numpy.typing import ArrayLike

    from astropy.cosmology._src.core import dataclass_decorator
    from astropy.cosmology._src.parameter import Parameter
    from astropy.cosmology._src.typing import FArray
    from astropy.cosmology._src.utils import aszarr
    from astropy.units import Quantity

    from . import scalar_inv_efuncs
    from .base import FLRW, FlatFLRWMixin

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

    @dataclass_decorator
    class w0wzCDM(FLRW):
        """FLRW cosmology with a variable dark energy EoS and curvature.

        The equation for the dark energy equation of state (EoS) uses the simple form:
        :math:`w(z) = w_0 + w_z z`.

        This form is not recommended for z > 1.

        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. This is pressure/density for
            dark energy in units where c=1.

        wz : float, optional
            Derivative of the dark energy equation of state with respect to z.
            A cosmological constant has w0=-1.0 and wz=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, optional
            Omega baryons: density of baryonic matter in units of the critical
            density at z=0.

        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 w0wzCDM
        >>> cosmo = w0wzCDM(H0=70, Om0=0.3, Ode0=0.7, w0=-0.9, wz=0.2)

        The comoving distance in Mpc at redshift z:

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

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

        def __post_init__(self) -> None:
            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.w0wzcdm_inv_efunc_norel
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ok0,
                    self.w0,
                    self.wz,
                )
            elif not self._nu_info.has_massive_nu:
                inv_efunc_scalar = scalar_inv_efuncs.w0wzcdm_inv_efunc_nomnu
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ok0,
                    self.Ogamma0 + self.Onu0,
                    self.w0,
                    self.wz,
                )
            else:
                inv_efunc_scalar = scalar_inv_efuncs.w0wzcdm_inv_efunc
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ok0,
                    self.Ogamma0,
                    self._nu_info.neff_per_nu,
                    self._nu_info.n_massless_nu,
                    self._nu_info.nu_y_list,
                    self.w0,
                    self.wz,
                )
            object.__setattr__(self, "_inv_efunc_scalar", inv_efunc_scalar)
            object.__setattr__(self, "_inv_efunc_scalar_args", inv_efunc_scalar_args)

        def w(self, z: Quantity | ArrayLike, /) -> FArray:
            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.

                .. versionchanged:: 8.0
                   z must be a positional argument.

            Returns
            -------
            w : ndarray
                The dark energy equation of state.

            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 given by :math:`w(z) = w_0 + w_z z`.
            """
            return self.w0 + self.wz * aszarr(z)

        def de_density_scale(self, z: Quantity | ArrayLike, /) -> FArray:
            r"""Evaluates the redshift dependence of the dark energy density.

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

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

                .. versionchanged:: 8.0
                   z must be a positional argument.

            Returns
            -------
            I : ndarray
                The scaling of the energy density of dark energy with redshift.

            References
            ----------
            .. [1] Linder, E. (2003). Exploring the Expansion History of the Universe.
                   Physics Review Letters, 90(9), 091301.

            Notes
            -----
            The scaling factor, I, is defined by :math:`\rho(z) = \rho_0 I`,
            and in this case is given by ([1]_)

            .. math::

               I = \left(1 + z\right)^{3 \left(1 + w_0 - w_z\right)}
                         \exp \left(3 w_z z\right)
            """
            z = aszarr(z)
            return (z + 1.0) ** (3.0 * (1.0 + self.w0 - self.wz)) * exp(3.0 * self.wz * z)

    @dataclass_decorator
    class Flatw0wzCDM(FlatFLRWMixin, w0wzCDM):
        """FLRW cosmology with a variable dark energy EoS and no curvature.

        The equation for the dark energy equation of state (EoS) uses the simple form:
        :math:`w(z) = w_0 + w_z z`.

        This form is not recommended for z > 1.

        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. This is pressure/density for
            dark energy in units where c=1.

        wz : float, optional
            Derivative of the dark energy equation of state with respect to z.
            A cosmological constant has w0=-1.0 and wz=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, optional
            Omega baryons: density of baryonic matter in units of the critical
            density at z=0.

        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 Flatw0wzCDM
        >>> cosmo = Flatw0wzCDM(H0=70, Om0=0.3, w0=-0.9, wz=0.2)

        The comoving distance in Mpc at redshift z:

        >>> cosmo.comoving_distance(0.5)
        <Quantity 1849.74726272 Mpc>
        """

        def __post_init__(self) -> None:
            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.fw0wzcdm_inv_efunc_norel
                inv_efunc_scalar_args = (self.Om0, self.Ode0, self.w0, self.wz)
            elif not self._nu_info.has_massive_nu:
                inv_efunc_scalar = scalar_inv_efuncs.fw0wzcdm_inv_efunc_nomnu
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ogamma0 + self.Onu0,
                    self.w0,
                    self.wz,
                )
            else:
                inv_efunc_scalar = scalar_inv_efuncs.fw0wzcdm_inv_efunc
                inv_efunc_scalar_args = (
                    self.Om0,
                    self.Ode0,
                    self.Ogamma0,
                    self._nu_info.neff_per_nu,
                    self._nu_info.n_massless_nu,
                    self._nu_info.nu_y_list,
                    self.w0,
                    self.wz,
                )
            object.__setattr__(self, "_inv_efunc_scalar", inv_efunc_scalar)
            object.__setattr__(self, "_inv_efunc_scalar_args", inv_efunc_scalar_args)