Inheritance diagram for lsst.ip.isr.photodiode.PhotodiodeCalib:

Public Member Functions
	__init__ (self, timeSamples=None, currentSamples=None, **kwargs)

	fromDict (cls, dictionary)

	toDict (self)

	fromTable (cls, tableList)

	toTable (self)

	readTwoColumnPhotodiodeData (cls, filename)

	integrate (self)

	integrateDirectSum (self)

	integrateTrimmedSum (self)

	integrateChargeSum (self)

Public Attributes
	timeSamples

	currentSamples

	integrationMethod

	currentScale

Static Protected Attributes
str	_OBSTYPE = 'PHOTODIODE'

str	_SCHEMA = 'Photodiode'

float	_VERSION = 1.0

Detailed Description

Independent current measurements from photodiode for linearity
calculations.

Parameters
----------
timeSamples : `list` or `numpy.ndarray`
    List of samples the photodiode was measured at.
currentSamples : `list` or `numpy.ndarray`
    List of current measurements at each time sample.
log : `lsst.log.Log`, optional
    Log to write messages to.
**kwargs :
    Additional parameters. These will be passed to the parent
    constructor with the exception of:

    ``"integrationMethod"``
        Name of the algorithm to use to integrate the current
        samples. Allowed values are ``DIRECT_SUM``,
        ``TRIMMED_SUM``, and ``CHARGE_SUM`` (`str`).
    ``"currentScale"``
        Scale factor to apply to the current samples for the
        ``CHARGE_SUM`` integration method. A typical value
        would be `-1`, to flip the sign of the integrated charge.

Definition at line 33 of file photodiode.py.

Constructor & Destructor Documentation

◆ init()

lsst.ip.isr.photodiode.PhotodiodeCalib.__init__	(		self,
			timeSamples = None,
			currentSamples = None,
		**	kwargs )

Reimplemented from lsst.ip.isr.calibType.IsrCalib.

Definition at line 63 of file photodiode.py.

    def __init__(self, timeSamples=None, currentSamples=None, **kwargs):
        if timeSamples is not None and currentSamples is not None:
            if len(timeSamples) != len(currentSamples):
                raise RuntimeError(f"Inconsitent vector lengths: {len(timeSamples)} vs {len(currentSamples)}")
            else:
                self.timeSamples = np.array(timeSamples).ravel()
                self.currentSamples = np.array(currentSamples).ravel()
        else:
            self.timeSamples = np.array([]).ravel()
            self.currentSamples = np.array([]).ravel()
 
        super().__init__(**kwargs)
 
        if 'integrationMethod' in kwargs:
            self.integrationMethod = kwargs.pop('integrationMethod')
        else:
            self.integrationMethod = 'DIRECT_SUM'
 
        if 'currentScale' in kwargs:
            self.currentScale = kwargs.pop('currentScale')
        else:
            self.currentScale = 1.0
 
        if 'day_obs' in kwargs:
            self.updateMetadata(day_obs=kwargs['day_obs'])
        if 'seq_num' in kwargs:
            self.updateMetadata(seq_num=kwargs['seq_num'])
 
        self.requiredAttributes.update(['timeSamples', 'currentSamples', 'integrationMethod'])
 

Member Function Documentation

◆ fromDict()

lsst.ip.isr.photodiode.PhotodiodeCalib.fromDict	(		cls,
			dictionary )

Construct a PhotodiodeCalib from a dictionary of properties.

Parameters
----------
dictionary : `dict`
    Dictionary of properties.

Returns
-------
calib : `lsst.ip.isr.PhotodiodeCalib`
    Constructed photodiode data.

Raises
------
RuntimeError
    Raised if the supplied dictionary is for a different
    calibration type.

Reimplemented from lsst.ip.isr.calibType.IsrCalib.

Definition at line 94 of file photodiode.py.

    def fromDict(cls, dictionary):
        """Construct a PhotodiodeCalib from a dictionary of properties.
 
        Parameters
        ----------
        dictionary : `dict`
            Dictionary of properties.
 
        Returns
        -------
        calib : `lsst.ip.isr.PhotodiodeCalib`
            Constructed photodiode data.
 
        Raises
        ------
        RuntimeError
            Raised if the supplied dictionary is for a different
            calibration type.
        """
        calib = cls()
 
        if calib._OBSTYPE != dictionary['metadata']['OBSTYPE']:
            raise RuntimeError(f"Incorrect photodiode supplied.  Expected {calib._OBSTYPE}, "
                               f"found {dictionary['metadata']['OBSTYPE']}")
 
        calib.setMetadata(dictionary['metadata'])
 
        calib.timeSamples = np.array(dictionary['timeSamples']).ravel()
        calib.currentSamples = np.array(dictionary['currentSamples']).ravel()
        calib.integrationMethod = dictionary.get('integrationMethod', "DIRECT_SUM")
 
        calib.updateMetadata()
        return calib
 

◆ fromTable()

lsst.ip.isr.photodiode.PhotodiodeCalib.fromTable	(		cls,
			tableList )

Construct calibration from a list of tables.

This method uses the `fromDict` method to create the
calibration after constructing an appropriate dictionary from
the input tables.

Parameters
----------
tableList : `list` [`astropy.table.Table`]
    List of tables to use to construct the crosstalk
    calibration.

Returns
-------
calib : `lsst.ip.isr.PhotodiodeCalib`
    The calibration defined in the tables.

Reimplemented from lsst.ip.isr.calibType.IsrCalib.

Definition at line 152 of file photodiode.py.

    def fromTable(cls, tableList):
        """Construct calibration from a list of tables.
 
        This method uses the `fromDict` method to create the
        calibration after constructing an appropriate dictionary from
        the input tables.
 
        Parameters
        ----------
        tableList : `list` [`astropy.table.Table`]
            List of tables to use to construct the crosstalk
            calibration.
 
        Returns
        -------
        calib : `lsst.ip.isr.PhotodiodeCalib`
            The calibration defined in the tables.
        """
        dataTable = tableList[0]
 
        metadata = dataTable.meta
        inDict = {}
        inDict['metadata'] = metadata
        inDict['integrationMethod'] = metadata.pop('INTEGRATION_METHOD', 'DIRECT_SUM')
 
        inDict['timeSamples'] = dataTable['TIME']
        inDict['currentSamples'] = dataTable['CURRENT']
 
        return cls().fromDict(inDict)
 

◆ integrate()

lsst.ip.isr.photodiode.PhotodiodeCalib.integrate ( self )

Integrate the current.

Raises
------
RuntimeError
    Raised if the integration method is not known.

Definition at line 231 of file photodiode.py.

    def integrate(self):
        """Integrate the current.
 
        Raises
        ------
        RuntimeError
            Raised if the integration method is not known.
        """
        if self.integrationMethod == 'DIRECT_SUM':
            return self.integrateDirectSum()
        elif self.integrationMethod == 'TRIMMED_SUM':
            return self.integrateTrimmedSum()
        elif self.integrationMethod == 'CHARGE_SUM':
            return self.integrateChargeSum()
        else:
            raise RuntimeError(f"Unknown integration method {self.integrationMethod}")
 

◆ integrateChargeSum()

lsst.ip.isr.photodiode.PhotodiodeCalib.integrateChargeSum ( self )

For this method, the values in .currentSamples are actually the
integrated charge values as measured by the ammeter for each
sampling interval.  We need to do a baseline subtraction,
based on the charge values when the LED is off, then sum up
the corrected signals.

Returns
-------
sum : `float`
    Total charge measured.

Definition at line 280 of file photodiode.py.

    def integrateChargeSum(self):
        """For this method, the values in .currentSamples are actually the
        integrated charge values as measured by the ammeter for each
        sampling interval.  We need to do a baseline subtraction,
        based on the charge values when the LED is off, then sum up
        the corrected signals.
 
        Returns
        -------
        sum : `float`
            Total charge measured.
        """
        dt = self.timeSamples[1:] - self.timeSamples[:-1]
        # The .currentSamples values are the current integrals over
        # the interval preceding the current time stamp, so omit the
        # first value.
        charge = self.currentScale*self.currentSamples[1:]
        # The current per interval to use for baseline subtraction
        # without assuming all of the dt values are the same:
        current = charge/dt
        # To determine the baseline current level, exclude points with
        # signal levels > 5% of the maximum (measured relative to the
        # overall minimum), and extend that selection 2 entries on
        # either side to avoid otherwise low-valued points that sample
        # the signal ramp and which should not be included in the
        # baseline estimate.
        dy = np.max(current) - np.min(current)
        signal, = np.where(current > dy/20. + np.min(current))
        imin = signal[0] - 2
        imax = signal[-1] + 2
        bg = np.concatenate([np.arange(0, imin), np.arange(imax, len(current))])
        bg_current = np.sum(charge[bg])/np.sum(dt[bg])
        # Return the background-subtracted total charge.
        return np.sum(charge - bg_current*dt)

◆ integrateDirectSum()

lsst.ip.isr.photodiode.PhotodiodeCalib.integrateDirectSum ( self )

Integrate points.

This uses numpy's trapezoidal integrator.

Returns
-------
sum : `float`
    Total charge measured.

Definition at line 248 of file photodiode.py.

    def integrateDirectSum(self):
        """Integrate points.
 
        This uses numpy's trapezoidal integrator.
 
        Returns
        -------
        sum : `float`
            Total charge measured.
        """
        return np.trapz(self.currentSamples, x=self.timeSamples)
 

◆ integrateTrimmedSum()

lsst.ip.isr.photodiode.PhotodiodeCalib.integrateTrimmedSum ( self )

Integrate points with a baseline level subtracted.

This uses numpy's trapezoidal integrator.

Returns
-------
sum : `float`
    Total charge measured.

See Also
--------
lsst.eotask.gen3.eoPtc

Definition at line 260 of file photodiode.py.

    def integrateTrimmedSum(self):
        """Integrate points with a baseline level subtracted.
 
        This uses numpy's trapezoidal integrator.
 
        Returns
        -------
        sum : `float`
            Total charge measured.
 
        See Also
        --------
        lsst.eotask.gen3.eoPtc
        """
        currentThreshold = ((max(self.currentSamples) - min(self.currentSamples))/5.0
                            + min(self.currentSamples))
        lowValueIndices = np.where(self.currentSamples < currentThreshold)
        baseline = np.median(self.currentSamples[lowValueIndices])
        return np.trapz(self.currentSamples - baseline, self.timeSamples)
 

◆ readTwoColumnPhotodiodeData()

lsst.ip.isr.photodiode.PhotodiodeCalib.readTwoColumnPhotodiodeData	(		cls,
			filename )

Construct a PhotodiodeCalib by reading the simple column format.

Parameters
----------
filename : `str`
    File to read samples from.

Returns
-------
calib : `lsst.ip.isr.PhotodiodeCalib`
    The calibration defined in the file.

Definition at line 207 of file photodiode.py.

    def readTwoColumnPhotodiodeData(cls, filename):
        """Construct a PhotodiodeCalib by reading the simple column format.
 
        Parameters
        ----------
        filename : `str`
            File to read samples from.
 
        Returns
        -------
        calib : `lsst.ip.isr.PhotodiodeCalib`
            The calibration defined in the file.
        """
        import os.path
 
        rawData = np.loadtxt(filename, dtype=[('time', 'float'), ('current', 'float')])
 
        basename = os.path.basename(filename)
        cleaned = os.path.splitext(basename)[0]
        _, _, day_obs, seq_num = cleaned.split("_")
 
        return cls(timeSamples=rawData['time'], currentSamples=rawData['current'],
                   day_obs=int(day_obs), seq_num=int(seq_num))
 

◆ toDict()

lsst.ip.isr.photodiode.PhotodiodeCalib.toDict ( self )

Return a dictionary containing the photodiode properties.

The dictionary should be able to be round-tripped through.
`fromDict`.

Returns
-------
dictionary : `dict`
    Dictionary of properties.

Reimplemented from lsst.ip.isr.calibType.IsrCalib.

Definition at line 128 of file photodiode.py.

    def toDict(self):
        """Return a dictionary containing the photodiode properties.
 
        The dictionary should be able to be round-tripped through.
        `fromDict`.
 
        Returns
        -------
        dictionary : `dict`
            Dictionary of properties.
        """
        self.updateMetadata()
 
        outDict = {}
        outDict['metadata'] = self.getMetadata()
 
        outDict['timeSamples'] = self.timeSamples.tolist()
        outDict['currentSamples'] = self.currentSamples.tolist()
 
        outDict['integrationMethod'] = self.integrationMethod
 
        return outDict
 

◆ toTable()

lsst.ip.isr.photodiode.PhotodiodeCalib.toTable ( self )

Construct a list of tables containing the information in this
calibration.

The list of tables should create an identical calibration
after being passed to this class's fromTable method.

Returns
-------
tableList : `list` [`astropy.table.Table`]
    List of tables containing the photodiode calibration
    information.

Reimplemented from lsst.ip.isr.calibType.IsrCalib.

Definition at line 182 of file photodiode.py.

    def toTable(self):
        """Construct a list of tables containing the information in this
        calibration.
 
        The list of tables should create an identical calibration
        after being passed to this class's fromTable method.
 
        Returns
        -------
        tableList : `list` [`astropy.table.Table`]
            List of tables containing the photodiode calibration
            information.
        """
        self.updateMetadata()
        catalog = Table([{'TIME': self.timeSamples,
                          'CURRENT': self.currentSamples}])
        inMeta = self.getMetadata().toDict()
        outMeta = {k: v for k, v in inMeta.items() if v is not None}
        outMeta.update({k: "" for k, v in inMeta.items() if v is None})
        outMeta['INTEGRATION_METHOD'] = self.integrationMethod
        catalog.meta = outMeta
 
        return [catalog]
 

Member Data Documentation

◆ _OBSTYPE

str lsst.ip.isr.photodiode.PhotodiodeCalib._OBSTYPE = 'PHOTODIODE'

staticprotected

Definition at line 59 of file photodiode.py.

◆ _SCHEMA

str lsst.ip.isr.photodiode.PhotodiodeCalib._SCHEMA = 'Photodiode'

staticprotected

Definition at line 60 of file photodiode.py.

◆ _VERSION

float lsst.ip.isr.photodiode.PhotodiodeCalib._VERSION = 1.0

staticprotected

Definition at line 61 of file photodiode.py.

◆ currentSamples

lsst.ip.isr.photodiode.PhotodiodeCalib.currentSamples

Definition at line 69 of file photodiode.py.

◆ currentScale

lsst.ip.isr.photodiode.PhotodiodeCalib.currentScale

Definition at line 82 of file photodiode.py.

◆ integrationMethod

lsst.ip.isr.photodiode.PhotodiodeCalib.integrationMethod

Definition at line 77 of file photodiode.py.

◆ timeSamples

lsst.ip.isr.photodiode.PhotodiodeCalib.timeSamples

Definition at line 68 of file photodiode.py.

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

/j/snowflake/release/lsstsw/stack/lsst-scipipe-8.0.0/Linux64/ip_isr/g02d81e74bb+fa3a7a026e/python/lsst/ip/isr/photodiode.py

Public Member Functions

Public Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ __init__()

Member Function Documentation

◆ fromDict()

◆ fromTable()

◆ integrate()

◆ integrateChargeSum()

◆ integrateDirectSum()

◆ integrateTrimmedSum()

◆ readTwoColumnPhotodiodeData()

◆ toDict()

◆ toTable()

Member Data Documentation

◆ _OBSTYPE

◆ _SCHEMA

◆ _VERSION

◆ currentSamples

◆ currentScale

◆ integrationMethod

◆ timeSamples

◆ init()