LoadReferenceCatalogTask

class lsst.pipe.tasks.loadReferenceCatalog.LoadReferenceCatalogTask(*, dataIds, refCats, name, **kwargs)

Bases: Task

Load multi-band reference objects from a reference catalog.

Parameters:
dataIdsiterable of lsst.daf.butler.dataId

An iterable object of dataIds which point to reference catalogs in a Gen3 repository. Required for Gen3.

refCatsiterable of lsst.daf.butler.DeferredDatasetHandle

An iterable object of dataset refs for reference catalogs in a Gen3 repository.

namestr

The name of the refcat that this object will load. This name is used for applying colorterms, for example.

Raises:
RuntimeError if dataIds or refCats is None.

Methods Summary

emptyMetadata()

Empty (clear) the metadata for this Task and all sub-Tasks.

getFullMetadata()

Get metadata for all tasks.

getFullName()

Get the task name as a hierarchical name including parent task names.

getName()

Get the name of the task.

getPixelBoxCatalog(bbox, wcs, filterList[, ...])

Get a multi-band reference catalog by specifying a bounding box and WCS.

getSkyCircleCatalog(center, radius, filterList)

Get a multi-band reference catalog by specifying a center and radius.

getTaskDict()

Get a dictionary of all tasks as a shallow copy.

makeField(doc)

Make a lsst.pex.config.ConfigurableField for this task.

makeSubtask(name, **keyArgs)

Create a subtask as a new instance as the name attribute of this task.

timer(name[, logLevel])

Context manager to log performance data for an arbitrary block of code.

Methods Documentation

emptyMetadata() → None

Empty (clear) the metadata for this Task and all sub-Tasks.

getFullMetadata() → TaskMetadata

Get metadata for all tasks.

Returns:
metadataTaskMetadata

The keys are the full task name. Values are metadata for the top-level task and all subtasks, sub-subtasks, etc.

Notes

The returned metadata includes timing information (if @timer.timeMethod is used) and any metadata set by the task. The name of each item consists of the full task name with . replaced by :, followed by . and the name of the item, e.g.:

topLevelTaskName:subtaskName:subsubtaskName.itemName

using : in the full task name disambiguates the rare situation that a task has a subtask and a metadata item with the same name.

getFullName() → str

Get the task name as a hierarchical name including parent task names.

Returns:
fullNamestr

The full name consists of the name of the parent task and each subtask separated by periods. For example:

  • The full name of top-level task “top” is simply “top”.

  • The full name of subtask “sub” of top-level task “top” is “top.sub”.

  • The full name of subtask “sub2” of subtask “sub” of top-level task “top” is “top.sub.sub2”.

getName() → str

Get the name of the task.

Returns:
taskNamestr

Name of the task.

See also

getFullName
getPixelBoxCatalog(bbox, wcs, filterList, epoch=None, bboxToSpherePadding=None)

Get a multi-band reference catalog by specifying a bounding box and WCS.

The catalog will be in numpy.ndarray, with positions proper-motion corrected to “epoch” (if specified, and if the reference catalog has proper motions); sources cut on a reference selector (if “config.doReferenceSelection = True”); and color-terms applied (if “config.doApplyColorTerms = True”).

The format of the reference catalog will be of the format:

dtype = [(‘ra’, ‘np.float64’),

(‘dec’, ‘np.float64’), (‘refMag’, ‘np.float32’, (len(filterList), )), (‘refMagErr’, ‘np.float32’, (len(filterList), ))]

Reference magnitudes (AB) and errors will be 99 for non-detections in a given band.

Parameters:
bboxlsst.geom.Box2I

Box which bounds a region in pixel space.

wcslsst.afw.geom.SkyWcs

Wcs object defining the pixel to sky (and reverse) transform for the supplied bbox.

filterListList [ str ]

List of camera physicalFilter names to retrieve magnitudes.

epochastropy.time.Time, optional

Epoch to which to correct proper motion and parallax (if available), or None to not apply such corrections.

bboxToSpherePaddingint, optional

Padding to account for translating a set of corners into a spherical (convex) boundary that is certain to encompass the entire area covered by the bbox.

Returns:
refCatnumpy.ndarray

Reference catalog.

getSkyCircleCatalog(center, radius, filterList, epoch=None, catalogFormat='numpy')

Get a multi-band reference catalog by specifying a center and radius.

The catalog will be in numpy.ndarray, with positions proper-motion corrected to “epoch” (if specified, and if the reference catalog has proper motions); sources cut on a reference selector (if “config.doReferenceSelection = True”); and color-terms applied (if “config.doApplyColorTerms = True”).

The format of the reference catalog will be of the format:

dtype = [(‘ra’, ‘np.float64’),

(‘dec’, ‘np.float64’), (‘refMag’, ‘np.float32’, (len(filterList), )), (‘refMagErr’, ‘np.float32’, (len(filterList), ))]

Reference magnitudes (AB) and errors will be 99 for non-detections in a given band.

Parameters:
centerlsst.geom.SpherePoint

Point defining the center of the circular region.

radiuslsst.geom.Angle

Defines the angular radius of the circular region.

filterListList [ str ]

List of camera physicalFilter names to retrieve magnitudes.

epochastropy.time.Time, optional

Epoch to which to correct proper motion and parallax (if available), or None to not apply such corrections.

Returns:
refCatnumpy.ndarray

Reference catalog.

getTaskDict() → dict[str, weakref.ReferenceType[lsst.pipe.base.task.Task]]

Get a dictionary of all tasks as a shallow copy.

Returns:
taskDictdict

Dictionary containing full task name: task object for the top-level task and all subtasks, sub-subtasks, etc.

classmethod makeField(doc: str) → ConfigurableField

Make a lsst.pex.config.ConfigurableField for this task.

Parameters:
docstr

Help text for the field.

Returns:
configurableFieldlsst.pex.config.ConfigurableField

A ConfigurableField for this task.

Examples

Provides a convenient way to specify this task is a subtask of another task.

Here is an example of use:

class OtherTaskConfig(lsst.pex.config.Config):
    aSubtask = ATaskClass.makeField("brief description of task")
makeSubtask(name: str, **keyArgs: Any) → None

Create a subtask as a new instance as the name attribute of this task.

Parameters:
namestr

Brief name of the subtask.

**keyArgs

Extra keyword arguments used to construct the task. The following arguments are automatically provided and cannot be overridden:

  • config.

  • parentTask.

Notes

The subtask must be defined by Task.config.name, an instance of ConfigurableField or RegistryField.

timer(name: str, logLevel: int = 10) → Iterator[None]

Context manager to log performance data for an arbitrary block of code.

Parameters:
namestr

Name of code being timed; data will be logged using item name: Start and End.

logLevel

A logging level constant.

See also

lsst.utils.timer.logInfo

Examples

Creating a timer context:

with self.timer("someCodeToTime"):
    pass  # code to time