DonutQuickMeasurementTask

class lsst.ts.wep.task.DonutQuickMeasurementTask(config, *, display=None, **kwargs)

Bases: QuickFrameMeasurementTask

Methods Summary

checkResult(exp, centroid, srcNum, percentile)	Perform a final check that centroid location is actually bright.
detectObjectsInExp(exp, nSigma, nPixMin[, grow])	Run a very basic but fast threshold-based object detection on an exposure Return the footPrintSet for the objects in a postISR exposure.
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(exp[, template, donutDiameter, ...])	Run method for the task.
timer(name[, logLevel])	Context manager to log performance data for an arbitrary block of code.

Methods Documentation

static checkResult(exp, centroid, srcNum, percentile)

Perform a final check that centroid location is actually bright.

Parameters

explsst.afw.image.Exposure

The exposure on which to operate

centroidtuple of float

Location of the centroid in pixel coordinates

scrNumint

Number of the source in the source catalog. Only used if the check is failed, for debug purposes.

percentilefloat

Image’s percentile above which the pixel containing the centroid must be in order to pass the check.

Raises

ValueError

Raised if the centroid’s pixel is not above the percentile threshold

static detectObjectsInExp(exp, nSigma, nPixMin, grow=0)

Run a very basic but fast threshold-based object detection on an exposure Return the footPrintSet for the objects in a postISR exposure.

Parameters

explsst.afw.image.Exposure

Image in which to detect objects.

nSigmafloat

nSigma above image’s stddev at which to set the detection threshold.

nPixMinint

Minimum number of pixels for detection.

growint

Grow the detected footprint by this many pixels.

Returns

footPrintSetlsst.afw.detection.FootprintSet

FootprintSet containing the detections.

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 : 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(exp, template=None, donutDiameter=None, cutoutPadding=None)

Run method for the task. This task runs a quick detection and measurement scheme to detect donuts in images based upon QuickFrameMeasurementTask.

Parameters

explsst.afw.image.Exposure

Post-ISR image with donut sources.

template: numpy.ndarray or None, optional

Donut template binary image. A template is required if doPreConvolution is True in configuration. (The Default is None.)

donutDiameterint or None, optional

Expected size of donut in pixels. If None then it will take this from the input configuration class. (The default is None.)

cutOutPaddingint or None, optional

Number of pixels to add in addition to donutDiameter when creating postage stamp for exact centroid measurement. If None it will take this from the input configuration class. (The default is None.)

Returns

structlsst.pipe.base.Struct

The struct contains the following data:

• detectedCatalogdict

  Dictionary of detected sources with location and flux measurements.

Raises

ValueError

Raised if template is None when doPreConvolution configuration parameter is set to True.

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.

Examples

Creating a timer context:

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

See Also

lsst.utils.timer.logInfo : Implementation function.