RegisterTask¶

Bases: Task

Task to register (align) multiple images.

The ‘run’ method provides a revised Wcs from matches and fitting sources. Additional methods are provided as a convenience to warp an exposure (‘warpExposure’) and sources (‘warpSources’) with the new Wcs.

Methods Summary

`emptyMetadata`()	Empty (clear) the metadata for this Task and all sub-Tasks.
`fitWcs`(matches, inputWcs, inputBBox)	Fit Wcs to matches.
`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.
`matchSources`(inputSources, templateSources)	Match sources between the input and template.
`run`(inputSources, inputWcs, inputBBox, ...)	Register (align) an input exposure to the template The sources must have RA,Dec set, and accurate to within the 'matchRadius' of the configuration in order to facilitate source matching.
`timer`(name[, logLevel])	Context manager to log performance data for an arbitrary block of code.
`warpExposure`(inputExp, newWcs, templateWcs, ...)	Warp input exposure to template frame.
`warpSources`(inputSources, newWcs, ...)	Warp sources to the new frame.

Methods Documentation

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

fitWcs(matches, inputWcs, inputBBox)¶

Fit Wcs to matches.

The fitting includes iterative sigma-clipping.

Parameters:

matcheslist: List of matches (first is target, second is input).
inputWcslsst.afw.geom.SkyWcs: Original input Wcs.
inputBBoxlsst.geom.Box: Bounding box of input exposure.

Returns:

wcs: lsst.afw.geom.SkyWcs: Wcs fitted to matches.

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, ReferenceType[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.

matchSources(inputSources, templateSources)¶

Match sources between the input and template.

The order of the input arguments matters (because the later Wcs fitting assumes a particular order).

Parameters:

inputSourceslsst.afw.table.SourceCatalog: Source catalog of the input frame.
templateSourceslsst.afw.table.SourceCatalog: Source of the target frame.

Returns:

matches: list: Match list.

run(inputSources, inputWcs, inputBBox, templateSources)¶

Register (align) an input exposure to the template The sources must have RA,Dec set, and accurate to within the ‘matchRadius’ of the configuration in order to facilitate source matching. We fit a new Wcs, but do NOT set it in the input exposure.

Parameters:

inputSourceslsst.afw.table.SourceCatalog: Sources from input exposure.
inputWcslsst.afw.geom.SkyWcs: Wcs of input exposure.
inputBBoxlsst.geom.Box: Bounding box of input exposure.
templateSourceslsst.afw.table.SourceCatalog: Sources from template exposure.

Returns:

resultlsst.pipe.base.Struct

Results as a struct with attributes:

matches: Matches between sources (list).
wcs: Wcs for input in frame of template (lsst.afw.geom.SkyWcs).

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.

Navigation

RegisterTask¶