PersistenceStep

class jwst.persistence.PersistenceStep(name=None, parent=None, config_file=None, _validate_kwds=True, **kws)[source]

Bases: JwstStep

Correct a science image for persistence.

Create a Step instance.

Parameters:

namestr: The name of the Step instance. Used in logging messages and in cache filenames. If not provided, one will be generated based on the class name.
parentStep: The parent step of this step. Used to determine a fully-qualified name for this step, and to determine the mode in which to run this step.
config_filestr or pathlib.Path: The path to the config file that this step was initialized with. Use to determine relative path names of other config files.
_validate_kwdsbool: Validate given kws against specs/config.
**kwsdict: Additional parameters to set. These will be set as member variables on the new Step instance.

Attributes Summary

`class_alias`
`spec`

Methods Summary

`get_persistence_array_from_file`(result, ...)	Get the persistence array from an ASDF file.
`process`(step_input)	Execute the persistence correction step.
`process_persistence_options`(result)	Process persistence_time, persistence_array, and persistence_dnu as the inputs.
`write_persistence_array`(result, filename)	Write the persistence array to an ASDF file.

Attributes Documentation

class_alias = 'persistence'

spec

save_persistence = string(default=None) # Name of ASDF output file to save the persistence array
persistence_time = integer(default=None) # Time, in seconds, to use for persistence window
dn_threshold = float(default=None) # A threshold above which to flag persistence.
persistence_array_file = string(default=None) # A path to an ASDF file containing a 2-D array of persistence times per pixel
persistence_dnu = boolean(default=False) # If True the set the DO_NOT_USE flag with PERSISTENCE
skip = boolean(default=True) # By default, skip the step.

Methods Documentation

get_persistence_array_from_file(result, nrows, ncols)[source]

Get the persistence array from an ASDF file.

Parameters:

nrowsint: The number of rows in the RampModel data.
ncolsint: The number of columns in the RampModel data.

process(step_input)[source]

Execute the persistence correction step.

Parameters:

step_inputRampModel or str: Input datamodel or file to be corrected

Returns:

resultRampModel: The persistence corrected datamodel

process_persistence_options(result)[source]

Process persistence_time, persistence_array, and persistence_dnu as the inputs.

Parameters:

resultRampModel: The RampModel on which to process the persistence flag.

Returns:

retstr or None: “Failed” if invalid persistence_time; otherwise NoneType.

write_persistence_array(result, filename)[source]

Write the persistence array to an ASDF file.

Parameters:

resultRampModel: The RampModel on which to process the persistence flag.