Step ArgumentsΒΆ

The extract_1d step has two step-specific arguments. Currently neither of these is used for IFU data.

  • --smoothing_length

If smoothing_length is greater than 1 (and is an odd integer), the background will be smoothed in the dispersion direction with a boxcar of this width. If smoothing_length is None (the default), the step will attempt to read the value from the reference file. If a value was specified in the reference file, that will be used. Note that in this case a different value can be specified for each slit. If no value was specified either by the user or in the reference file, no background smoothing will be done.

  • --bkg_order

This is the order of a polynomial function to be fit to the background regions. The fit is done independently for each column (or row, if the dispersion is vertical) of the input image, and the fitted curve will be subtracted from the target data. bkg_order = 0 (the minimum allowed value) means to fit a constant. The user-supplied value (if any) overrides the value in the reference file. If neither is specified, a value of 0 will be used.