Satellite azimuth angles may be losing precision when ill-conditioned, and should be restricted to [-180, 180]

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Satellite azimuth angles may be losing precision when ill-conditioned, and should be restricted to [-180, 180] #304

Closed gerritholl closed 5 years ago

gerritholl commented 5 years ago

@cbulgin reports that satellite azimuth angles at times look strange:

Certainly, they should be restricted to [-180, 180] like solar azimuth angles. But there are also some other discontinuities that may not correspond to what one would expect, should investigate.

gerritholl commented 5 years ago

There are also missing angles, which is bad and should not happen.

gerritholl commented 5 years ago

This shows satellite azimuth angles in a more easily readable form, after normalising to [0, 360], visualised with a cyclic colormap

gerritholl commented 5 years ago

Actually, it should be in [0, 360].

From the CF standard names:

Platform azimuth angle is the horizontal angle between the line of sight from the observation point to the platform and a reference direction at the observation point, which is often due north. The angle is measured clockwise positive, starting from the reference direction.

gerritholl commented 5 years ago

On the other hand, I don't need the -180 offset, which just confuses things.

gerritholl commented 5 years ago