DirectMatchTask

class lsst.meas.astrom.DirectMatchTask(refObjLoader=None, **kwargs)

Bases: Task

Simple, brute force matching of a source catalog to a reference catalog.

Parameters:
butlerNone

Compatibility parameter. Should not be used.

refObjLoaderlsst.meas.algorithms.ReferenceObjectLoader or None

A reference object loader object; gen3 pipeline tasks will pass None and call setRefObjLoader in runQuantum.

**kwargs

Other keyword arguments required for instantiating a Task (such as config).

Methods Summary

calculateCircle(catalog)

Calculate a circle enclosing the catalog.

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.

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(catalog[, filterName, epoch])

Load reference objects and match to them.

setRefObjLoader(refObjLoader)

Set the reference object loader for the task.

timer(name[, logLevel])

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

Methods Documentation

calculateCircle(catalog)

Calculate a circle enclosing the catalog.

Parameters:
cataloglsst.afw.table.SourceCatalog

Catalog to encircle.

Returns:
resultlsst.pipe.base.Struct

Result struct with components:

center

ICRS center coordinate (lsst.afw.geom.SpherePoint).

radius

Radius of the circle (lsst.geom.Angle).

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
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.

run(catalog, filterName=None, epoch=None)

Load reference objects and match to them.

Parameters:
cataloglsst.afw.table.SourceCatalog

Catalog to match.

filterNamestr

Name of filter loading fluxes.

epochastropy.time.Time or None

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

Returns:
resultlsst.pipe.base.Struct

Result struct with components:

matches

Matched sources with associated reference (lsst.afw.table.SourceMatchVector).

matchMeta

Match metadata (lsst.meas.astrom.MatchMetadata).

setRefObjLoader(refObjLoader)

Set the reference object loader for the task.

Parameters:
refObjLoaderlsst.meas.algorithms.ReferenceObjectLoader

An instance of a reference object loader.

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.

Examples

Creating a timer context:

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