Source code for ctapipe.coordinates

"""
Coordinates.
"""
import warnings

from astropy.coordinates import (
    CIRS,
    AltAz,
    FunctionTransformWithFiniteDifference,
    frame_transform_graph,
)

from .camera_frame import CameraFrame, EngineeringCameraFrame
from .ground_frames import (
    EastingNorthingFrame,
    GroundFrame,
    TiltedGroundFrame,
    project_to_ground,
)
from .impact_distance import impact_distance, shower_impact_distance
from .nominal_frame import NominalFrame
from .telescope_frame import TelescopeFrame
from .utils import altaz_to_righthanded_cartesian

__all__ = [
    "TelescopeFrame",
    "CameraFrame",
    "EngineeringCameraFrame",
    "NominalFrame",
    "GroundFrame",
    "TiltedGroundFrame",
    "EastingNorthingFrame",
    "MissingFrameAttributeWarning",
    "project_to_ground",
    "altaz_to_righthanded_cartesian",
    "impact_distance",
    "shower_impact_distance",
]


[docs]class MissingFrameAttributeWarning(Warning): pass
# astropy requires all AltAz to have locations # and obstimes so they can be converted into true skycoords # Also it is required to transform one AltAz into another one # This forbids it to use AltAz without setting location and obstime # here, the astropy behaviour is defined so that it is assumed, # that if no information about location or obstime is known, both are the same @frame_transform_graph.transform(FunctionTransformWithFiniteDifference, AltAz, AltAz) def altaz_to_altaz(from_coo, to_frame): # check if coordinates have obstimes defined obstime = from_coo.obstime if from_coo.obstime is None: warnings.warn( "AltAz coordinate has no obstime, assuming same frame", MissingFrameAttributeWarning, ) obstime = to_frame.obstime location = from_coo.location if from_coo.obstime is None: warnings.warn( "Horizontal coordinate has no location, assuming same frame", MissingFrameAttributeWarning, ) location = to_frame.location if obstime is None or location is None: return to_frame.realize_frame(from_coo.data) return from_coo.transform_to(CIRS(obstime=obstime)).transform_to(to_frame)