BrighterFatterKernel¶
- class lsst.ip.isr.BrighterFatterKernel(camera=None, level=None, **kwargs)¶
Bases:
IsrCalib
Calibration of brighter-fatter kernels for an instrument.
ampKernels are the kernels for each amplifier in a detector, as generated by having
level == 'AMP'
.detectorKernel is the kernel generated for a detector as a whole, as generated by having
level == 'DETECTOR'
.makeDetectorKernelFromAmpwiseKernels is a method to generate the kernel for a detector, constructed by averaging together the ampwise kernels in the detector. The existing application code is only defined for kernels with
level == 'DETECTOR'
, so this method is used if the supplied kernel was built withlevel == 'AMP'
.- Parameters:
- camera
lsst.afw.cameraGeom.Camera
Camera describing detector geometry.
- level
str
Level the kernels will be generated for.
- log
logging.Logger
, optional Log to write messages to.
- **kwargs
Parameters to pass to parent constructor.
- camera
Notes
Version 1.1 adds the
expIdMask
property, and substitutesmeans
andvariances
forrawMeans
andrawVariances
from the PTC dataset.- expIdMask
dict
, [str
,`numpy.ndarray`] Dictionary keyed by amp names containing the mask produced after outlier rejection.
- rawMeans
dict
, [str
,numpy.ndarray
] Dictionary keyed by amp names containing the unmasked average of the means of the exposures in each flat pair.
- rawVariances
dict
, [str
,numpy.ndarray
] Dictionary keyed by amp names containing the variance of the difference image of the exposures in each flat pair. Corresponds to rawVars of PTC.
- rawXcorrs
dict
, [str
,numpy.ndarray
] Dictionary keyed by amp names containing an array of measured covariances per mean flux. Corresponds to covariances of PTC.
- badAmps
list
List of bad amplifiers names.
- shape
tuple
Tuple of the shape of the BFK kernels.
- gain
dict
, [str
,`float`] Dictionary keyed by amp names containing the fitted gains.
- noise
dict
, [str
,`float`] Dictionary keyed by amp names containing the fitted noise.
- meanXcorrs
dict
, [str
,`numpy.ndarray`] Dictionary keyed by amp names containing the averaged cross-correlations.
- valid
dict
, [str
,`bool`] Dictionary keyed by amp names containing validity of data.
- ampKernels
dict
, [str
,numpy.ndarray
] Dictionary keyed by amp names containing the BF kernels.
- detKernels
dict
Dictionary keyed by detector names containing the BF kernels.
Attributes Summary
Methods Summary
apply
(target)Method to apply the calibration to the target object.
calibInfoFromDict
(dictionary)Handle common keywords.
determineCalibClass
(metadata, message)Attempt to find calibration class in metadata.
fromDetector
(detector)Modify the calibration parameters to match the supplied detector.
fromDict
(dictionary)Construct a calibration from a dictionary of properties.
fromTable
(tableList)Construct calibration from a list of tables.
Return the set of lengths needed for reshaping components.
Retrieve metadata associated with this calibration.
initFromCamera
(camera[, detectorId])Initialize kernel structure from camera.
makeDetectorKernelFromAmpwiseKernels
(...[, ...])Average the amplifier level kernels to create a detector level kernel.
readFits
(filename, **kwargs)Read calibration data from a FITS file.
readText
(filename, **kwargs)Read calibration representation from a yaml/ecsv file.
repackCorrelations
(amp, correlationShape)If the correlations were masked, they need to be repacked into the correct shape.
replaceDetectorKernelWithAmpKernel
(ampName, ...)setMetadata
(metadata)Store a copy of the supplied metadata with this calibration.
toDict
()Return a dictionary containing the calibration properties.
toTable
()Construct a list of tables containing the information in this calibration.
updateMetadata
([setDate])Update calibration metadata.
updateMetadataFromExposures
(exposures)Extract and unify metadata information.
validate
([other])Validate that this calibration is defined and can be used.
writeFits
(filename)Write calibration data to a FITS file.
writeText
(filename[, format])Write the calibration data to a text file.
Attributes Documentation
- requiredAttributes¶
Methods Documentation
- apply(target)¶
Method to apply the calibration to the target object.
- calibInfoFromDict(dictionary)¶
Handle common keywords.
This isn’t an ideal solution, but until all calibrations expect to find everything in the metadata, they still need to search through dictionaries.
- Parameters:
- dictionary
dict
orlsst.daf.base.PropertyList
Source for the common keywords.
- dictionary
- Raises:
- RuntimeError
Raised if the dictionary does not match the expected OBSTYPE.
- classmethod determineCalibClass(metadata, message)¶
Attempt to find calibration class in metadata.
- Parameters:
- Returns:
- calibClass
object
The class to use to read the file contents. Should be an
lsst.ip.isr.IsrCalib
subclass.
- calibClass
- Raises:
- ValueError
Raised if the resulting calibClass is the base
lsst.ip.isr.IsrClass
(which does not implement the content methods).
- fromDetector(detector)¶
Modify the calibration parameters to match the supplied detector.
- Parameters:
- detector
lsst.afw.cameraGeom.Detector
Detector to use to set parameters from.
- detector
- Raises:
- NotImplementedError
Raised if not implemented by a subclass. This needs to be implemented by subclasses for each calibration type.
- classmethod fromDict(dictionary)¶
Construct a calibration from a dictionary of properties.
- Parameters:
- dictionary
dict
Dictionary of properties.
- dictionary
- Returns:
- calib
lsst.ip.isr.BrighterFatterKernel
Constructed calibration.
- calib
- Raises:
- RuntimeError
Raised if the supplied dictionary is for a different calibration. Raised if the version of the supplied dictionary is 1.0.
- classmethod fromTable(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 brighter-fatter calibration.
- tableList
- Returns:
- calib
lsst.ip.isr.BrighterFatterKernel
The calibration defined in the tables.
- calib
- getLengths()¶
Return the set of lengths needed for reshaping components.
- getMetadata()¶
Retrieve metadata associated with this calibration.
- Returns:
- meta
lsst.daf.base.PropertyList
Metadata. The returned
PropertyList
can be modified by the caller and the changes will be written to external files.
- meta
- initFromCamera(camera, detectorId=None)¶
Initialize kernel structure from camera.
- Parameters:
- camera
lsst.afw.cameraGeom.Camera
Camera to use to define geometry.
- detectorId
int
, optional Index of the detector to generate.
- camera
- Returns:
- calib
lsst.ip.isr.BrighterFatterKernel
The initialized calibration.
- calib
- Raises:
- RuntimeError
Raised if no detectorId is supplied for a calibration with
level='AMP'
.
- makeDetectorKernelFromAmpwiseKernels(detectorName, ampsToExclude=[])¶
Average the amplifier level kernels to create a detector level kernel. There is no change in index ordering/orientation from this averaging.
- classmethod readFits(filename, **kwargs)¶
Read calibration data from a FITS file.
- Parameters:
- Returns:
- calib
lsst.ip.isr.IsrCalib
Calibration contained within the file.
- calib
- classmethod readText(filename, **kwargs)¶
Read calibration representation from a yaml/ecsv file.
- Parameters:
- Returns:
- calib
IsrCalibType
Calibration class.
- calib
- Raises:
- RuntimeError
Raised if the filename does not end in “.ecsv” or “.yaml”.
- repackCorrelations(amp, correlationShape)¶
If the correlations were masked, they need to be repacked into the correct shape.
- replaceDetectorKernelWithAmpKernel(ampName, detectorName)¶
- setMetadata(metadata)¶
Store a copy of the supplied metadata with this calibration.
- Parameters:
- metadata
lsst.daf.base.PropertyList
Metadata to associate with the calibration. Will be copied and overwrite existing metadata.
- metadata
- toDict()¶
Return a dictionary containing the calibration properties.
The dictionary should be able to be round-tripped through
fromDict
.- Returns:
- dictionary
dict
Dictionary of properties.
- dictionary
- toTable()¶
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
[lsst.afw.table.Table
] List of tables containing the crosstalk calibration information.
- tableList
- updateMetadata(setDate=False, **kwargs)¶
Update calibration metadata.
This calls the base class’s method after ensuring the required calibration keywords will be saved.
- Parameters:
- setDate
bool
, optional Update the CALIBDATE fields in the metadata to the current time. Defaults to False.
- kwargs
Other keyword parameters to set in the metadata.
- setDate
- updateMetadataFromExposures(exposures)¶
Extract and unify metadata information.
- Parameters:
- exposures
list
Exposures or other calibrations to scan.
- exposures
- validate(other=None)¶
Validate that this calibration is defined and can be used.
- writeFits(filename)¶
Write calibration data to a FITS file.
- writeText(filename, format='auto')¶
Write the calibration data to a text file.
- Parameters:
- Returns:
- used
str
The name of the file used to write the data. This may differ from the input if the format is explicitly chosen.
- used
- Raises:
- RuntimeError
Raised if filename does not end in a known extension, or if all information cannot be written.
Notes
The file is written to YAML/ECSV format and will include any associated metadata.