SkyPixSystem

class lsst.daf.butler.SkyPixSystem(name: str, *, maxLevel: int, PixelizationClass: Type[lsst.sphgeom.pixelization_abc.PixelizationABC])

Bases: lsst.daf.butler.TopologicalFamily

Class for hierarchical pixelization of the sky.

A TopologicalFamily that represents a hierarchical pixelization of the sky.

Parameters:

name : str

Name of the system.

maxLevel : int

Maximum level (inclusive) of the hierarchy.

PixelizationClass : type (lsst.sphgeom.PixelizationABC subclass)

Class whose instances represent a particular level of this pixelization.

Methods Summary

choose(endpoints)

Select the best member of this family to use.

Methods Documentation

choose(endpoints: lsst.daf.butler.core.named.NamedValueAbstractSet[lsst.daf.butler.core._topology.TopologicalRelationshipEndpoint]) → lsst.daf.butler.core.dimensions._skypix.SkyPixDimension

Select the best member of this family to use.

These are to be used in a query join or data ID when more than one is present.

Usually this should correspond to the most fine-grained region.

Parameters:

endpoints : NamedValueAbstractSet [TopologicalRelationshipEndpoint]

Endpoints to choose from. May include endpoints that are not members of this family (which should be ignored).

Returns:

best : TopologicalRelationshipEndpoint

The best endpoint that is both a member of self and in endpoints.