ResampleStep¶
- class jwst.resample.resample_step.ResampleStep(name=None, parent=None, config_file=None, _validate_kwds=True, **kws)[source]¶
Bases:
JwstStep
Resample input data onto a regular grid using the drizzle algorithm.
Note
When supplied via
output_wcs
, a custom WCS overrides other custom WCS parameters such asoutput_shape
(now computed from byoutput_wcs.bounding_box
),crpix
- Parameters:
input (JwstDataModel or Association) – Single filename for either a single image or an association table.
Create a
Step
instance.- Parameters:
name (str, optional) – 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.
parent (Step instance, optional) – 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_file (str path, optional) – The path to the config file that this step was initialized with. Use to determine relative path names of other config files.
**kws (dict) – Additional parameters to set. These will be set as member variables on the new Step instance.
Attributes Summary
Methods Summary
get_drizpars
(ref_filename, input_models)Extract drizzle parameters from reference file.
process
(input)This is where real work happens.
update_fits_wcs
(model)Update FITS WCS keywords of the resampled image.
Attributes Documentation
- class_alias = 'resample'¶
- reference_file_types = ['drizpars']¶
- spec¶
pixfrac = float(default=1.0) # change back to None when drizpar reference files are updated kernel = string(default='square') # change back to None when drizpar reference files are updated fillval = string(default='INDEF' ) # change back to None when drizpar reference files are updated weight_type = option('ivm', 'exptime', None, default='ivm') # change back to None when drizpar ref update output_shape = int_list(min=2, max=2, default=None) # [x, y] order crpix = float_list(min=2, max=2, default=None) crval = float_list(min=2, max=2, default=None) rotation = float(default=None) pixel_scale_ratio = float(default=1.0) # Ratio of input to output pixel scale pixel_scale = float(default=None) # Absolute pixel scale in arcsec output_wcs = string(default='') # Custom output WCS. single = boolean(default=False) blendheaders = boolean(default=True) allowed_memory = float(default=None) # Fraction of memory to use for the combined image. in_memory = boolean(default=True)
Methods Documentation
- get_drizpars(ref_filename, input_models)[source]¶
Extract drizzle parameters from reference file.
This method extracts parameters from the drizpars reference file and uses those to set defaults on the following ResampleStep configuration parameters:
pixfrac = float(default=None) kernel = string(default=None) fillval = string(default=None) wht_type = option(‘ivm’, ‘exptime’, None, default=None)
Once the defaults are set from the reference file, if the user has used a resample.cfg file or run ResampleStep using command line args, then these will overwrite the defaults pulled from the reference file.