lsst.pipe.tasks.exampleStatsTasks.ExampleSimpleStatsTask Class Reference

Example task to compute mean and standard deviation of an image. More...

Inheritance diagram for lsst.pipe.tasks.exampleStatsTasks.ExampleSimpleStatsTask:

Public Member Functions
def	run
	Compute and return statistics for a masked image. More...

Static Public Attributes
	ConfigClass = pexConfig.Config
	Even a task with no configuration requires setting ConfigClass. More...

Private Attributes
	_statsControl

Static Private Attributes
string	_DefaultName = "exampleSimpleStats"
	Having a default name simplifies construction of the task, since the parent task need not specify a name. More...

Detailed Description

Example task to compute mean and standard deviation of an image.

Contents

• Description
• Configuration parameters
• Debug variables
• A complete example of using ExampleSimpleStatsTask

Description

Example task to compute mean and standard deviation of an image.

This was designed to be run as a subtask by ExampleCmdLineTask. It is about as simple as a task can be; it has no configuration parameters and requires no special initialization. See also ExampleSigmaClippedStatsTask as a variant that is slightly more complicated.

The main method is run.

Configuration parameters

This task has no configuration parameters.

Debug variables

This task has no debug variables.

A complete example of using ExampleSimpleStatsTask

This code is in examples/exampleStatsTask.py (this one example runs both ExampleSigmaClippedStatsTask and ExampleSimpleStatsTask), and can be run as:

examples/exampleStatsTask.py [fitsFile]

Definition at line 142 of file exampleStatsTasks.py.

Member Function Documentation

def lsst.pipe.tasks.exampleStatsTasks.ExampleSimpleStatsTask.run	(		self,
			maskedImage
	)

Compute and return statistics for a masked image.

Parameters

[in]

maskedImage:

masked image (an lsst::afw::MaskedImage)

Returns

a pipeBase Struct containing:

• mean: mean of image plane
• meanErr: uncertainty in mean
• stdDev: standard deviation of image plane
• stdDevErr: uncertainty in standard deviation

Definition at line 191 of file exampleStatsTasks.py.

    def run(self, maskedImage):
        """!Compute and return statistics for a masked image

        @param[in] maskedImage: masked image (an lsst::afw::MaskedImage)
        @return a pipeBase Struct containing:
        - mean: mean of image plane
        - meanErr: uncertainty in mean
        - stdDev: standard deviation of image plane
        - stdDevErr: uncertainty in standard deviation
        """
        self._statsControl = afwMath.StatisticsControl()
        statObj = afwMath.makeStatistics(maskedImage, afwMath.MEAN | afwMath.STDEV | afwMath.ERRORS,
            self._statsControl)
        mean, meanErr = statObj.getResult(afwMath.MEAN)
        stdDev, stdDevErr = statObj.getResult(afwMath.STDEV)
        self.log.info("simple mean=%0.2f; meanErr=%0.2f; stdDev=%0.2f; stdDevErr=%0.2f" % \
            (mean, meanErr, stdDev, stdDevErr))

        return pipeBase.Struct(
            mean = mean,
            meanErr = meanErr,
            stdDev = stdDev,
            stdDevErr = stdDevErr,
        )

Member Data Documentation

string lsst.pipe.tasks.exampleStatsTasks.ExampleSimpleStatsTask._DefaultName = "exampleSimpleStats"

staticprivate

Having a default name simplifies construction of the task, since the parent task need not specify a name.

Note: having a default name is required for command-line tasks. The name can be simple and need not be unique (except for multiple subtasks that will be run by a parent task at the same time).

Definition at line 184 of file exampleStatsTasks.py.

lsst.pipe.tasks.exampleStatsTasks.ExampleSimpleStatsTask._statsControl

private

Definition at line 201 of file exampleStatsTasks.py.

lsst.pipe.tasks.exampleStatsTasks.ExampleSimpleStatsTask.ConfigClass = pexConfig.Config

static

Even a task with no configuration requires setting ConfigClass.

Definition at line 179 of file exampleStatsTasks.py.

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The documentation for this class was generated from the following file:

• /home/lsstsw/stack/Linux64/pipe_tasks/11.0-2-g818369d/python/lsst/pipe/tasks/exampleStatsTasks.py