interpolate_spectral_element

stsynphot.spectrum.interpolate_spectral_element(parfilename, interpval, ext=1)[source]

Interpolate (or extrapolate) throughput spectra in given parameterized FITS table to given parameter value.

FITS table is parsed with stsynphot.stio.read_interp_spec(). Parameterized values must be in ascending order in the table columns.

If extrapolation is needed but not allowed, default throughput from THROUGHPUT column will be used.

Parameters
parfilenamestr

Parameterized filename contains a suffix followed by a column name specificationin between square brackets. For example, path/acs_fr656n_006_syn.fits[fr656n#].

interpvalfloat

Desired parameter value.

extint, optional

FITS extension index of the data table.

Returns
spsynphot.spectrum.SpectralElement

Empirical bandpass at interpval.

Raises
synphot.exceptions.ExtrapolationNotAllowed

Extrapolation is not allowed by data table.

synphot.exceptions.SynphotError

No columns available for interpolation or extrapolation.