healpix convolve does not preserve header information

[joshuarwood]

gdt-core/src/gdt/core/healpix.py

Line 106 in 018acb3

return type(self).from_data(new_hpx, trigtime=self.trigtime, **kwargs)

Currently trigtime is the only property saved when returning a HealPix-derived class from the convolve function.

In practice, this means a user trying to convolve a systematic error with a GBM map will receive a map with header, scpos, and quaternion information stripped away. Is this the intended behavior? Should users be expected to re-apply that information to the returned map?

[AdamGoldstein-USRA]

I'm not sure we want to require passing of that information, especially if it doesn't exist for some scenario/mission. But this does highlight an oversight that this method should have been overwritten in the GbmHealPix class. In that method, it would be appropriate to pass the header, quaternion, and sc position. Should open an issue in gdt-fermi.

[joshuarwood]

Yeah, I completely agree after looking at this in more detail over the afternoon. The issue I'm having relates more to the buggy / inconsistent header behavior reported in your latest merge: USRA-STI/gdt-fermi@ad6c3c3

I'll try the latest main branch to see if it solves the issues I'm having. I'll close out this issue.