MatchOptimisticBTask¶

class lsst.meas.astrom.MatchOptimisticBTask(**kwargs)¶

Bases: lsst.pipe.base.Task

Match sources to reference objects using the Optimistic Pattern Matcher B algorithm of Tabur 2007.

Methods Summary

`emptyMetadata`()	Empty (clear) the metadata for this Task and all sub-Tasks.
`filterStars`(refCat)	Extra filtering pass; subclass if desired.
`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.
`matchObjectsToSources`(refCat, sourceCat, …)	Match sources to position reference stars.
`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.

filterStars(refCat)¶

Extra filtering pass; subclass if desired.

Parameters:	refCat : `lsst.afw.table.SimpleCatalog` Catalog of reference objects.
Returns:	trimmedRefCat : `lsst.afw.table.SimpleCatalog` Reference catalog with some filtering applied. Currently no filtering is applied.

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

getTaskDict() → Dict[str, weakref.ReferenceType[lsst.pipe.base.task.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.

matchObjectsToSources(refCat, sourceCat, wcs, sourceFluxField, refFluxField, match_tolerance=None)¶

Match sources to position reference stars.

Parameters:

refCat : lsst.afw.table.SimpleCatalog: Reference catalog to match.
sourceCat : lsst.afw.table.SourceCatalog: Catalog of sources found on an exposure. This should already be down-selected to “good”/”usable” sources in the calling Task.
wcs : lsst.afw.geom.SkyWcs: Current WCS of the exposure containing the sources.
sourceFluxField : str: Field of the sourceCat to use for flux
refFluxField : str: Field of the refCat to use for flux
match_tolerance : lsst.meas.astrom.MatchTolerance: Object containing information from previous lsst.meas.astrom.AstrometryTask match/fit cycles for use in matching. If None is config defaults.

Returns:

matchResult : lsst.pipe.base.Struct

Result struct with components

matches : List of matches with distance below the maximum match distance (list of lsst.afw.table.ReferenceMatch).
useableSourceCat : Catalog of sources matched and suited for WCS fitting (lsst.afw.table.SourceCatalog).
match_tolerance : MatchTolerance object updated from this match iteration (lsst.meas.astrom.MatchTolerance).

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.

Navigation

MatchOptimisticBTask¶