GetDcrTemplateTask

class lsst.ip.diffim.GetDcrTemplateTask(*args, **kwargs)

Bases: lsst.ip.diffim.GetTemplateTask

Attributes Summary

canMultiprocess

Methods Summary

checkPatchList(patchList)	Check that all of the DcrModel subfilters are present for each patch.
emptyMetadata()	Empty (clear) the metadata for this Task and all sub-Tasks.
getAllSchemaCatalogs()	Get schema catalogs for all tasks in the hierarchy, combining the results into a single dict.
getDcrModel(patchList, coaddRefs, visitInfo)	Build DCR-matched coadds from a list of exposure references.
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.
getOverlappingExposures(inputs)	Return lists of coadds and their corresponding dataIds that overlap the detector.
getResourceConfig()	Return resource configuration for this task.
getSchemaCatalogs()	Get the schemas generated by this task.
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.
run(coaddExposures, bbox, wcs, dataIds, **kwargs)	Warp coadds from multiple tracts to form a template for image diff.
runQuantum(butlerQC, inputRefs, outputRefs)	Method to do butler IO and or transforms to provide in memory objects for tasks run method
timer(name, logLevel)	Context manager to log performance data for an arbitrary block of code.

Attributes Documentation

canMultiprocess = True

Methods Documentation

checkPatchList(patchList)

Check that all of the DcrModel subfilters are present for each patch.

Parameters:

patchList : dict

Dict of the patches containing valid data for each tract

Raises:

RuntimeError

If the number of exposures found for a patch does not match the number of subfilters.

emptyMetadata() → None

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

getAllSchemaCatalogs() → Dict[str, Any]

Get schema catalogs for all tasks in the hierarchy, combining the results into a single dict.

Returns:

schemacatalogs : dict

Keys are butler dataset type, values are a empty catalog (an instance of the appropriate lsst.afw.table Catalog type) for all tasks in the hierarchy, from the top-level task down through all subtasks.

Notes

This method may be called on any task in the hierarchy; it will return the same answer, regardless.

The default implementation should always suffice. If your subtask uses schemas the override Task.getSchemaCatalogs, not this method.

getDcrModel(patchList, coaddRefs, visitInfo)

Build DCR-matched coadds from a list of exposure references.

Parameters:

patchList : dict

Dict of the patches containing valid data for each tract

coaddRefs : list of elements of type

lsst.daf.butler.DeferredDatasetHandle of lsst.afw.image.Exposure

Data references to DcrModels that overlap the detector.

visitInfo : lsst.afw.image.VisitInfo

Metadata for the science image.

Returns:

`list` of elements of type `lsst.afw.image.Exposure`

Coadd exposures that overlap the detector.

getFullMetadata() → lsst.pipe.base._task_metadata.TaskMetadata

Get metadata for all tasks.

Returns:

metadata : TaskMetadata

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:

fullName : str

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:

taskName : str

Name of the task.

See also

getFullName

getOverlappingExposures(inputs)

Return lists of coadds and their corresponding dataIds that overlap the detector.

The spatial index in the registry has generous padding and often supplies patches near, but not directly overlapping the detector. Filters inputs so that we don’t have to read in all input coadds.

Parameters:

inputs : dict of task Inputs, containing:

• coaddExposureRefs : list of elements of type

  lsst.daf.butler.DeferredDatasetHandle of lsst.afw.image.Exposure

  Data references to exposures that might overlap the detector.

• bbox : lsst.geom.Box2I

  Template Bounding box of the detector geometry onto which to resample the coaddExposures

• skyMap : lsst.skymap.SkyMap

  Input definition of geometry/bbox and projection/wcs for template exposures

• wcs : lsst.afw.geom.SkyWcs

  Template WCS onto which to resample the coaddExposures

• visitInfo : lsst.afw.image.VisitInfo

  Metadata for the science image.

Returns:

result : lsst.pipe.base.Struct containing these fields:

• coaddExposures : list of elements of type lsst.afw.image.Exposure

  Coadd exposures that overlap the detector.

• dataIds : list of lsst.daf.butler.DataCoordinate

  Data IDs of the coadd exposures that overlap the detector.

Raises:

NoWorkFound

Raised if no patches overlatp the input detector bbox

getResourceConfig() → Optional[ResourceConfig]

Return resource configuration for this task.

Returns:

Object of type `~config.ResourceConfig` or ``None`` if resource

configuration is not defined for this task.

getSchemaCatalogs() → Dict[str, Any]

Get the schemas generated by this task.

Returns:

schemaCatalogs : dict

Keys are butler dataset type, values are an empty catalog (an instance of the appropriate lsst.afw.table Catalog type) for this task.

See also

Task.getAllSchemaCatalogs

Notes

Warning

Subclasses that use schemas must override this method. The default implementation returns an empty dict.

This method may be called at any time after the Task is constructed, which means that all task schemas should be computed at construction time, not when data is actually processed. This reflects the philosophy that the schema should not depend on the data.

Returning catalogs rather than just schemas allows us to save e.g. slots for SourceCatalog as well.

getTaskDict() → Dict[str, weakref.ReferenceType[Task]]

Get a dictionary of all tasks as a shallow copy.

Returns:

taskDict : dict

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

classmethod makeField(doc: str) → lsst.pex.config.configurableField.ConfigurableField

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

Parameters:

doc : str

Help text for the field.

Returns:

configurableField : lsst.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) → None

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

Parameters:

name : str

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.

run(coaddExposures, bbox, wcs, dataIds, **kwargs)

Warp coadds from multiple tracts to form a template for image diff.

Where the tracts overlap, the resulting template image is averaged. The PSF on the template is created by combining the CoaddPsf on each template image into a meta-CoaddPsf.

Parameters:

coaddExposures : list of lsst.afw.image.Exposure

Coadds to be mosaicked

bbox : lsst.geom.Box2I

Template Bounding box of the detector geometry onto which to resample the coaddExposures

wcs : lsst.afw.geom.SkyWcs

Template WCS onto which to resample the coaddExposures

dataIds : list of lsst.daf.butler.DataCoordinate

Record of the tract and patch of each coaddExposure.

**kwargs

Any additional keyword parameters.

Returns:

result : lsst.pipe.base.Struct containing

• outputExposure : a template coadd exposure assembled out of patches

runQuantum(butlerQC, inputRefs, outputRefs)

Method to do butler IO and or transforms to provide in memory objects for tasks run method

Parameters:

butlerQC : ButlerQuantumContext

A butler which is specialized to operate in the context of a lsst.daf.butler.Quantum.

inputRefs : InputQuantizedConnection

Datastructure whose attribute names are the names that identify connections defined in corresponding PipelineTaskConnections class. The values of these attributes are the lsst.daf.butler.DatasetRef objects associated with the defined input/prerequisite connections.

outputRefs : OutputQuantizedConnection

Datastructure whose attribute names are the names that identify connections defined in corresponding PipelineTaskConnections class. The values of these attributes are the lsst.daf.butler.DatasetRef objects associated with the defined output connections.

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

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

Parameters:

name : str

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

logLevel

A logging level constant.

See also

timer.logInfo

Examples

Creating a timer context:

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