Get instantaneous clock offset from SP3 ephemeris

Hi. I am working with multiple SP3 files to get satellite position from GPS data, and I have encountered an issue pulling the clock offset data. I had no problem creating an array of BoundedPropagators for each of the GPS satellites, and I can pull the interpolated position/velocity as a function of time… but as far as I can tell there is no interpolated clock offset value. Now I can pull a list of SP3Coordinate values from the SP3Ephemeris and each of those coordinate values will have a clock offset value attached, but there is no interpolation. And yes the clock offset changes slowly enough that pulling the clock offset from the closest AbsoluteDate value would probably suffice numerically, but that would be annoying and a workaround. Can anyone give me a straightforward way to get this data instantaneously as a function of time that I have missed? Thank you.

Hi @baubin

As part of solving issue 1049 and issue 1190, I am completely revamping the SP3 data hierarchy.
This work is almost completed, I expect to push it perhaps later today or over the week-end. The code is complete, I need to test it.

So I would suggest you to refrain for digging too deep into the current design, it will be obsoleted very soon. In fact, I introduced for SP3 what exists also for other file types like CCSDS, with SP3 being a container for SP3Header and a map of SP3Ephemeris (which are not inner classes anymore but independent classes), and SP3Ephemeris now contains several new SP3Segment, to cope with missing data in the files (this is to fix issue 1190).

Please open a new issue for the clock interpolation problem, I will fix it at the same time.

I will notify you in this thread when the new design is in the development branch so you can give it a try.

I have created issue 1191 and solved it.

It should now be in the develop branch. Beware it is at the tip of a big set of incompatible changes.

@luc Thanks so much. I will pull this and take a look.

Just to be clear, do you still need me to open an issue? From the text of issue 1191 I would say no.

No, you don’t have to create a separate issue. I did it myself in order to get a proper issue number while I was working on the git history.

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