from stdatamodels.jwst import datamodels
from ..stpipe import Step
from . import ami_analyze
__all__ = ["AmiAnalyzeStep"]
[docs]
class AmiAnalyzeStep(Step):
"""Performs analysis of an AMI mode exposure by applying the LG algorithm.
"""
class_alias = "ami_analyze"
spec = """
oversample = integer(default=3, min=1) # Oversampling factor
rotation = float(default=0.0) # Rotation initial guess [deg]
psf_offset = string(default='0.0 0.0') # Psf offset values to use to create the model array
rotation_search = string(default='-3 3 1') # Rotation search parameters: start, stop, step
"""
reference_file_types = ['throughput']
[docs]
def process(self, input):
"""
Performs analysis of an AMI mode exposure by applying the LG algorithm.
Parameters
----------
input: string
input file name
Returns
-------
result: AmiLgModel object
AMI image to which the LG fringe detection has been applied
"""
# Retrieve the parameter values
oversample = self.oversample
rotate = self.rotation
# pull out parameters that are strings and change to floats
psf_offset = [float(a) for a in self.psf_offset.split()]
rotsearch_parameters = [float(a) for a in self.rotation_search.split()]
self.log.info(f'Oversampling factor = {oversample}')
self.log.info(f'Initial rotation guess = {rotate} deg')
self.log.info(f'Initial values to use for psf offset = {psf_offset}')
# Open the input data model
try:
input_model = datamodels.ImageModel(input)
except ValueError as err:
raise RuntimeError(f"{err}. Input must be a 2D ImageModel.")
# check for 2D data array
if len(input_model.data.shape) != 2:
raise RuntimeError("Only 2D ImageModel data can be processed")
# Get the name of the filter throughput reference file to use
throughput_reffile = self.get_reference_file(input_model, 'throughput')
self.log.info(f'Using filter throughput reference file {throughput_reffile}')
# Check for a valid reference file
if throughput_reffile == 'N/A':
self.log.warning('No THROUGHPUT reference file found')
self.log.warning('AMI analyze step will be skipped')
raise RuntimeError("No throughput reference file found. "
"ami_analyze cannot continue.")
# Open the filter throughput reference file
throughput_model = datamodels.ThroughputModel(throughput_reffile)
# Apply the LG+ methods to the data
result = ami_analyze.apply_LG_plus(input_model, throughput_model,
oversample, rotate,
psf_offset,
rotsearch_parameters)
# Close the reference file and update the step status
throughput_model.close()
result.meta.cal_step.ami_analyze = 'COMPLETE'
return result