[coords] Question - Time domain coordinates and frames

[CresitelloDittmar, Mark]

On Thu, Apr 12, 2018 at 5:18 PM, Arnold Rots <arots at cfa.harvard.edu> wrote:

> No, the timeOrigin is only REQUIRED in a TimeFrame if it is referenced by
> a TimeOffset.
> So, both the TimeOffset and the timeOrigin can (and should!) refer to the
> same TimeFrame.
> (they should, because specifying the origin in a different TimeFrame is
> asking for trouble)
>
>
So, when a client reads a TimeOffset with timeOrigin, loads that (MJD) and
sees it references the same TimeFrame with a timeOrigin (itself), what is
the client supposed to do?
Since timeOrigin is only REQUIRED for TimeOffset, can I have a data column
that is Time in MJD, and have it refer to a TimeFrame with a TimeOrigin?
If so, what does the client do with that since MJD is absolute?


> It does mean that TimeOffsets that use different timeOrigins need to
> reference different TimeFrames.
> That is not a problem, since most TimeOffset-based time series will use
> the same timeOrigin.
>
>   - Arnold
>
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