SimpleAssociationTask¶

Bases: Task

Construct DiaObjects from a DataFrame of DIASources by spatially associating the sources.

Represents a simple, brute force algorithm, 2-way matching of DiaSources into. DiaObjects. Algorithm picks the nearest, first match within the matching radius of a DiaObject to associate a source to for simplicity.

Methods Summary

`addNewDiaObject`(diaSrc, diaSources, visit, ...)	Create a new DiaObject and append its data.
`createDiaObject`(objId, ra, dec)	Create a simple empty DiaObject with location and id information.
`emptyMetadata`()	Empty (clear) the metadata for this Task and all sub-Tasks.
`findMatches`(src_ra, src_dec, tol, hpIndices, ...)	Search healPixels around DiaSource locations for DiaObjects.
`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`(diaSources[, idGenerator])	Associate DiaSources into a collection of DiaObjects using a brute force matching algorithm.
`timer`(name[, logLevel])	Context manager to log performance data for an arbitrary block of code.
`updateCatalogs`(matchIndex, diaSrc, ...)	Update DiaObject and DiaSource values after an association.

Methods Documentation

addNewDiaObject(diaSrc, diaSources, visit, detector, diaSourceId, diaObjCat, idCat, diaObjCoords, healPixIndices)¶

Create a new DiaObject and append its data.

Parameters:

diaSrcpandas.Series

Full unassociated DiaSource to create a DiaObject from.

diaSourcespandas.DataFrame: DiaSource catalog to update information in. The catalog is modified in place. Must be indexed on: (visit, detector), diaSourceId.
visit, detectorint: Visit and detector ids where diaSrc was observed.

diaSourceIdint

Unique identifier of the DiaSource.

diaObjectCatlist of `dict`s: Catalog of diaObjects to append the new object o.
idCatlsst.afw.table.SourceCatalog: Catalog with the IdFactory used to generate unique DiaObject identifiers.
diaObjectCoordslist of `list`s of `lsst.geom.SpherePoint`s: Set of coordinates of DiaSource locations that make up the DiaObject average coordinate.
healPixIndiceslist of `int`s: HealPix indices representing the locations of each currently existing DiaObject.

createDiaObject(objId, ra, dec)¶

Create a simple empty DiaObject with location and id information.

Parameters:

objIdint: Unique ID for this new DiaObject.
rafloat: RA location of this DiaObject.
decfloat: Dec location of this DiaObject

Returns:

DiaObjectdict: Dictionary of values representing a DiaObject.

emptyMetadata() → None¶: Empty (clear) the metadata for this Task and all sub-Tasks.

findMatches(src_ra, src_dec, tol, hpIndices, diaObjs)¶

Search healPixels around DiaSource locations for DiaObjects.

Parameters:

src_rafloat: DiaSource RA location.
src_decfloat: DiaSource Dec location.
tolfloat: Size of annulus to convert to covering healPixels and search for DiaObjects.
hpIndiceslist of `int`s: List of heal pix indices containing the DiaObjects in diaObjs.
diaObjslist of `dict`s: Catalog diaObjects to with full location information for comparing to DiaSources.

Returns:

resultslsst.pipe.base.Struct

Results struct containing

dists: Array of distances between the current DiaSource diaObjects. (numpy.ndarray or None)
matches: Array of array indices of diaObjects this DiaSource matches to. (numpy.ndarray or None)

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: Get the full name of the task.

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(diaSources, idGenerator=None)¶

Associate DiaSources into a collection of DiaObjects using a brute force matching algorithm.

Reproducible for the same input data is assured by ordering the DiaSource data by visit,detector.

Parameters:

diaSourcespandas.DataFrame: DiaSources in clusters of visit, detector to spatially associate into DiaObjects.
idGeneratorlsst.meas.base.IdGenerator, optional: Object that generates Object IDs and random number generator seeds.

Returns:

resultslsst.pipe.base.Struct

Results struct with attributes:

assocDiaSources: Table of DiaSources with updated values for the DiaObjects they are spatially associated to (pandas.DataFrame).
diaObjects: Table of DiaObjects from matching DiaSources (pandas.DataFrame).

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.
logLevelint: A logging level constant.

Navigation

SimpleAssociationTask¶