RefCatalogInterface

class lsst.ts.wep.task.RefCatalogInterface(boresightRa, boresightDec, boresightRotAng)

Bases: object

Class to provide tools to interact with reference catalog in Butler repository and select pieces of the catalog that cover the sky area of a pointing.

Parameters:

• boresightRa (float) – Boresight RA in degrees.

• boresightDec (float) – Boresight Dec in degrees.

• boresightRotAng (float) – Boresight rotation angle in degreees.

Methods Summary

getDataRefs(htmIds, butler, catalogName, ...)	Get the butler references and dataIds for the reference catalog shards specified.
getDetectorWcs(detector)	Create a WCS for the detector with the initialized pointing information.
getHtmIds([radius])	Get the htmIds for the pieces of the reference catalog that overlap the circular area within radius (in degrees) of the boresight pointing.

Methods Documentation

getDataRefs(htmIds, butler, catalogName, collections)

Get the butler references and dataIds for the reference catalog shards specified.

Parameters:

• htmIds (array) – HtmIds for the shards of the reference catalog we need.

• butler (lsst.daf.butler.Butler) – Butler instance pointing at the repo with the reference catalog.

• catalogName (str) – Name of the reference catalog in the repository.

• collections (str or list of str) – Collections in the repository with the reference catalog.

Return type:

tuple[list, list]

Returns:

• list – List of the deferred dataset references pointing to the pieces of the reference catalog we want in the butler.

• list – List of the dataIds for the reference catalog shards.

getDetectorWcs(detector)

Create a WCS for the detector with the initialized pointing information.

Parameters:

detector (lsst.afw.cameraGeom.Detector) – Detector for which we want to generate a source catalog.

Returns:

Wcs object defining the pixel to sky (and inverse) transform for the supplied detector.

Return type:

lsst.afw.geom.SkyWcs

getHtmIds(radius=1.8)

Get the htmIds for the pieces of the reference catalog that overlap the circular area within radius (in degrees) of the boresight pointing. HtmIds are the spatial indices identifying hierarchical triangular mesh (HTM) shards that are used to store the reference catalogs in gen3 butler repositories in more easily accessible pieces.

Parameters:

radius (float, optional) – Radius in degrees of the pointing footprint. (the default is 1.8 degrees, enough to cover one LSST pointing.)

Returns:

Array of htmIds in the butler for the pieces of the reference catalog that overlap the pointing.

Return type:

numpy.ndarray