Instrument function causes the absorption to be split across adjacent spectra points (think sliding window). This means that you can't simply sample at a more coarse interval, but need to simulate at the more fine interval and then down sample. For fitting, I think this would mean adding something to increase the inflate the sampling interval and then resample onto the original frequency grid. In this implementation need to check that it can still accommodate gaps in the spectra and that the the output spectra isn't dependent on the inflation factor.
Instrument function causes the absorption to be split across adjacent spectra points (think sliding window). This means that you can't simply sample at a more coarse interval, but need to simulate at the more fine interval and then down sample. For fitting, I think this would mean adding something to increase the inflate the sampling interval and then resample onto the original frequency grid. In this implementation need to check that it can still accommodate gaps in the spectra and that the the output spectra isn't dependent on the inflation factor.