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# Source code for astropy.coordinates.builtin_frames.ecliptic

    # -*- coding: utf-8 -*-
    # Licensed under a 3-clause BSD style license - see LICENSE.rst
    from __future__ import (absolute_import, unicode_literals, division,
                            print_function)

    from ..representation import SphericalRepresentation
    from ..baseframe import BaseCoordinateFrame, TimeFrameAttribute
    from .utils import EQUINOX_J2000

    __all__ = ['GeocentricTrueEcliptic', 'BarycentricTrueEcliptic', 'HeliocentricTrueEcliptic']

    class GeocentricTrueEcliptic(BaseCoordinateFrame):
        """
        Geocentric ecliptic coordinates.  These origin of the coordinates are the
        geocenter (Earth), with the x axis pointing to the *true* (not mean) equinox
        at the time specified by the ``equinox`` attribute, and the xy-plane in the
        plane of the ecliptic for that date.

        Be aware that the definition of "geocentric" here means that this frame
        *includes* light deflection from the sun, aberration, etc when transforming
        to/from e.g. ICRS.

        This frame has one frame attribute:

        * ``equinox``
            The date to assume for this frame.  Determines the location of the
            x-axis and the location of the Earth (necessary for transformation to
            non-geocentric systems).

        .. warning::
            In the current version of astropy, the ecliptic frames do not yet have
            stringent accuracy tests.  We recommend you test to "known-good" cases
            to ensure this frames are what you are looking for. (and then ideally
            you would contribute these tests to Astropy!)

        Parameters
        ----------
        representation : `BaseRepresentation` or None
            A representation object or None to have no data (or use the other keywords)
        lon : `Angle`, optional, must be keyword
            The ecliptic longitude for this object (``lat`` must also be given and
            ``representation`` must be None).
        lat : `Angle`, optional, must be keyword
            The ecliptic latitude for this object (``lon`` must also be given and
            ``representation`` must be None).
        distance : `~astropy.units.Quantity`, optional, must be keyword
            The Distance for this object from the geocenter.
            (``representation`` must be None).
        """
        default_representation = SphericalRepresentation

        equinox = TimeFrameAttribute(default=EQUINOX_J2000)

    class BarycentricTrueEcliptic(BaseCoordinateFrame):
        """
        Barycentric ecliptic coordinates.  These origin of the coordinates are the
        barycenter of the solar system, with the x axis pointing in the direction of
        the *true* (not mean) equinox as at the time specified by the ``equinox``
        attribute (as seen from Earth), and the xy-plane in the plane of the
        ecliptic for that date.

        This frame has one frame attribute:

        * ``equinox``
            The date to assume for this frame.  Determines the location of the
            x-axis and the location of the Earth and Sun.

        .. warning::
            In the current version of astropy, the ecliptic frames do not yet have
            stringent accuracy tests.  We recommend you test to "known-good" cases
            to ensure this frames are what you are looking for. (and then ideally
            you would contribute these tests to Astropy!)

        Parameters
        ----------
        representation : `BaseRepresentation` or None
            A representation object or None to have no data (or use the other keywords)
        l : `Angle`, optional, must be keyword
            The ecliptic longitude for this object (``b`` must also be given and
            ``representation`` must be None).
        b : `Angle`, optional, must be keyword
            The ecliptic latitude for this object (``l`` must also be given and
            ``representation`` must be None).
        r : `~astropy.units.Quantity`, optional, must be keyword
            The Distance for this object from the sun's center.
            (``representation`` must be None).
        """
        default_representation = SphericalRepresentation

        equinox = TimeFrameAttribute(default=EQUINOX_J2000)

    class HeliocentricTrueEcliptic(BaseCoordinateFrame):
        """
        Heliocentric ecliptic coordinates.  These origin of the coordinates are the
        center of the sun, with the x axis pointing in the direction of
        the *true* (not mean) equinox as at the time specified by the ``equinox``
        attribute (as seen from Earth), and the xy-plane in the plane of the
        ecliptic for that date.

        This frame has one frame attribute:

        * ``equinox``
            The date to assume for this frame.  Determines the location of the
            x-axis and the location of the Earth and Sun.

        .. warning::
            In the current version of astropy, the ecliptic frames do not yet have
            stringent accuracy tests.  We recommend you test to "known-good" cases
            to ensure this frames are what you are looking for. (and then ideally
            you would contribute these tests to Astropy!)

        Parameters
        ----------
        representation : `BaseRepresentation` or None
            A representation object or None to have no data (or use the other keywords)
        l : `Angle`, optional, must be keyword
            The ecliptic longitude for this object (``b`` must also be given and
            ``representation`` must be None).
        b : `Angle`, optional, must be keyword
            The ecliptic latitude for this object (``l`` must also be given and
            ``representation`` must be None).
        r : `~astropy.units.Quantity`, optional, must be keyword
            The Distance for this object from the sun's center.
            (``representation`` must be None).
        """
        default_representation = SphericalRepresentation

        equinox = TimeFrameAttribute(default=EQUINOX_J2000)