IsrStatisticsTask¶

class lsst.ip.isr.IsrStatisticsTask(statControl=None, **kwargs)¶

Bases: Task

Task to measure arbitrary statistics on ISR processed exposures.

The goal is to wrap a number of optional measurements that are useful for calibration production and detector stability.

Methods Summary

`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.
`makeKernel`(kernelSize)	Make a boxcar smoothing kernel.
`makeSubtask`(name, **keyArgs)	Create a subtask as a new instance as the `name` attribute of this task.
`measureBanding`(inputExp, overscans)	Task to measure banding statistics.
`measureCti`(inputExp, overscans, gains)	Task to measure CTI statistics.
`measureProjectionStatistics`(inputExp, overscans)	Task to measure metrics from image slicing.
`run`(inputExp[, ptc, overscanResults])	Task to run arbitrary statistics.
`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.

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")

static makeKernel(kernelSize)¶

Make a boxcar smoothing kernel.

Parameters:

kernelSizeint: Size of the kernel in pixels.

Returns:

kernelnp.array: Kernel for boxcar smoothing.

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.

measureBanding(inputExp, overscans)¶

Task to measure banding statistics.

Parameters:

inputExplsst.afw.image.Exposure

Exposure to measure.

overscanslist [lsst.pipe.base.Struct]

List of overscan results. Expected fields are:

imageFit: Value or fit subtracted from the amplifier image data (scalar or lsst.afw.image.Image).
overscanFit: Value or fit subtracted from the overscan image data (scalar or lsst.afw.image.Image).
overscanImage: Image of the overscan region with the overscan correction applied (lsst.afw.image.Image). This quantity is used to estimate the amplifier read noise empirically.

Returns:

outputStatsdict [str, [dict [str,`float]]: Dictionary of measurements, keyed by amplifier name and statistics segment.

measureCti(inputExp, overscans, gains)¶

Task to measure CTI statistics.

Parameters:

inputExplsst.afw.image.Exposure

Exposure to measure.

overscanslist [lsst.pipe.base.Struct]

List of overscan results. Expected fields are:

imageFit: Value or fit subtracted from the amplifier image data (scalar or lsst.afw.image.Image).
overscanFit: Value or fit subtracted from the overscan image data (scalar or lsst.afw.image.Image).
overscanImage: Image of the overscan region with the overscan correction applied (lsst.afw.image.Image). This quantity is used to estimate the amplifier read noise empirically.

gainsdict [str float]

Dictionary of per-amplifier gains, indexed by amplifier name.

Returns:

outputStatsdict [str, [dict [str,`float]]: Dictionary of measurements, keyed by amplifier name and statistics segment.

measureProjectionStatistics(inputExp, overscans)¶

Task to measure metrics from image slicing.

Parameters:

inputExplsst.afw.image.Exposure

Exposure to measure.

overscanslist [lsst.pipe.base.Struct]

List of overscan results. Expected fields are:

imageFit: Value or fit subtracted from the amplifier image data (scalar or lsst.afw.image.Image).
overscanFit: Value or fit subtracted from the overscan image data (scalar or lsst.afw.image.Image).
overscanImage: Image of the overscan region with the overscan correction applied (lsst.afw.image.Image). This quantity is used to estimate the amplifier read noise empirically.

Returns:

outputStatsdict [str, [dict [str,`float]]: Dictionary of measurements, keyed by amplifier name and statistics segment.

run(inputExp, ptc=None, overscanResults=None, **kwargs)¶

Task to run arbitrary statistics.

The statistics should be measured by individual methods, and add to the dictionary in the return struct.

Parameters:

inputExplsst.afw.image.Exposure

The exposure to measure.

ptclsst.ip.isr.PtcDataset, optional

A PTC object containing gains to use.

overscanResultslist [lsst.pipe.base.Struct], optional

List of overscan results. Expected fields are:

imageFit: Value or fit subtracted from the amplifier image data (scalar or lsst.afw.image.Image).
overscanFit: Value or fit subtracted from the overscan image data (scalar or lsst.afw.image.Image).
overscanImage: Image of the overscan region with the overscan correction applied (lsst.afw.image.Image). This quantity is used to estimate the amplifier read noise empirically.

Returns:

resultStructlsst.pipe.base.Struct: Contains the measured statistics as a dict stored in a field named results.

Raises:

RuntimeError: Raised if the amplifier gains could not be found.

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

IsrStatisticsTask¶