Instrument packs: Incorrect coefficients for NIRSpec resolution

[drvdputt]

The resolution returned by pahfit.instrument.resolution is not correct, at least not for nirspec. Looking at this plot https://jwst-docs.stsci.edu/files/97979440/97979452/1/1596073265647/jwst_nirspec_g140h_disp.png, from this page https://jwst-docs.stsci.edu/jwst-near-infrared-spectrograph/nirspec-instrumentation/nirspec-dispersers-and-filters#NIRSpecDispersersandFilters-DispersioncurvesfortheNIRSpecdispersers, it should be around 1500 at 0.8 micron, for G140H. Instead we get

>>> instrument.resolution('jwst.nirspec.g140.high', 0.8)
3490.42860832

These are the coefficients from the instrument pack:

            coefficients: [2291.3574, 1404.4167, 88.98144, 36.30806]

The zeroth order coefficient seems too high.

[jdtsmith]

Ok actually the fits were fine, but the dumb auto domain/range stuff from numpy.polynomial.Polynomial were interfering. They rescale the input values (here wavelength).

[jdtsmith]

See #236 (please check it over!).

[drvdputt]

This might need to be reopened for the ISO resolution. I found this in the SWS handbook

But the resolution function is giving me this

>>> resolution("iso.sws.speed2.*", [3, 5, 10, 16, 25])
masked_array(
  data=[[1677, --, --],
        [1608, --, --],
        [1570, --, --],
        [1406, --, --],
        [993, --, --]],
  mask=[[False,  True,  True],
        [False,  True,  True],
        [False,  True,  True],
        [False,  True,  True],
        [False,  True,  True]],
  fill_value=999999)

I found this while looking at the included SWS data pahfit/data/ISO_SWS/Orion_D5_ISO-SWS_merged.ipac, and doing a fit. This data is supposedly AOT1 speed 2 (is this the same as SWS01 speed 2?), but the lines seem to narrow.

Manually hacking the resolution to 500 (as stated in the readme for the ISO files) makes the fit much better.