Chris Simpson

I think you misunderstand. This refers specifically to the recipes that make flatfields and can take a list of raw lamp frames and a list of raw darks to subtract....

This looks like a problem with the default python datatype being 64-bit, which IRAF can't handle. I don't think we ever require 64-bit integers or floats, so there is a...

Thanks for writing this down in a clear way. I think your `evaluate()` method (and also `__call__()` and `invert()`) should accept the `output_level` keyword and pass it down to (eventually)...

OK, there's quite a bit more needed and I don't understand some of the code so I'm struggling to write a PR to fix this bug. All these things should...

> There is an API difference __call__ does not accept things like astropy.coordinates objects while invert does. That call turns the astropy.coordinates objects into arrays. Why do `__call__()` and `invert()`...

> My suggestion is that if possible you should call one of these functions rather than the __call__ or invert. That's a significant refactor of our code. I don't see...

Perhaps I'm not clear about what you mean by "native API", but I thought this was clarified in #561, that the `output_level` keyword would control what gets returned (by default...

Within the confines of what's being discussed here, I think the output should always be at the same "level" as the input. Numerical inputs return numbers, Quantity inputs return Quantities,...

Just to check we're on the same page, I view "HLO" as meaning "HLO where possible, otherwise Quantity" -- for a standard spectral datacube, I would consider "HLO" to mean`(SkyCoord,...

Ah yes, I forgot about `SpectralCoord`, thanks (DRAGONS doesn't use it because it's newer than our initial spectroscopy code). Is there a `TimeCoord` if the data being represented is a...