Stream¶

class trackstream.Stream(data: astropy.table.QTable, origin: trackstream._type_hints.FrameType, data_err: Optional[astropy.table.Table] = None, *, frame: Optional[Union[trackstream._type_hints.FrameType, astropy.coordinates.SkyCoord]] = None)[source]¶

Bases: object

A Stellar Stream.

Parameters

dataTable
originICRS: The origin point of the rotated reference frame.
data_errQTable (optional): The data_err must have (at least) column names [“x_err”, “y_err”, “z_err”]
frameBaseCoordinateFrame or None (optional, keyword-only): The stream frame. Locally linearizes the data. If not None, need to fit for the frame (default).

Attributes Summary

`arm1`
`arm2`
`coords`	Coordinates.
`data_coords`	Get `coord` from data table.
`data_frame`	The frame of the data.
`frame`	Alias for `system_frame`.
`number_of_tails`	Number of tidal tails.
`system_frame`	A system-centric frame.
`track`	Stream track.

Methods Summary

`fit_track`([arm1SOM, arm2SOM, force])	Make a stream track.
`predict_track`([affine, angular])

Attributes Documentation

arm1¶

arm2¶

coords¶: Coordinates.

data_coords¶: Get coord from data table.

data_frame¶: The frame of the data.

frame¶: Alias for system_frame.

number_of_tails¶

Number of tidal tails.

Returns

number_of_tailsint: There can only be 1, or 2 tidal tails.

system_frame¶

A system-centric frame.

Determined from the argument frame at initialization. If None (default) and the method fit has been called, then a system frame has been found and cached.

track¶

Stream track.

Raises

ValueError: If track is not fit.

Methods Documentation

fit_track(arm1SOM: Optional[trackstream.preprocess.som.SelfOrganizingMap1D] = None, arm2SOM: Optional[trackstream.preprocess.som.SelfOrganizingMap1D] = None, *, force: bool = False, **kwargs) → StreamTrack[source]¶

Make a stream track.

Parameters

arm1SOM, arm2SOMSelfOrganizingMap (optional, keyword-only): Fiducial SOMs for stream arms 1 and 2, respectively.
forcebool: Whether to force a fit, even if already fit.
**kwargs: Passed to trackstream.TrackStream.fit().

Returns

trackstream.StreamTrack

predict_track(affine: Optional[astropy.units.quantity.Quantity] = None, angular: bool = False) → trackstream.utils.path.path_moments[source]¶

Navigation

Stream¶