Easy cadence search?

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I’ve been trying to use the RSP to query a 14-day sample of DP0.3 in some region densely populated with visits/data, but I don’t have a good understanding of where the telescope points in (ra, dec) as a function of MJD, and so I’ve mostly just been making some guesses. I think this would be a lot easier if there was a way to easily query the cadence history (simulation in this case) via the RSP – to query the exposures in a time period and see what small region might be optimal for my use case. Personally / in this situation, I can grab the cadence simulation that was used to generate DP0.3 externally, but for general DP0 use + for the actual survey, a table with cadence information could be very useful. Does the fact that different DP0 data products were generated with different cadences get in the way of including this information?

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Very good point, I 100% agree. It’d be good to have a ‘Visits’ table alongside the other ones.

As raised at the PCW, it would be great if we could have access to the pointing database (the database currently output by rubin_sim/rubin scheduler ) on the RSP for things like this and some of the other cases I mentioned as we’re already as a community getting used to using it for cadence analysis. Here’s the schema.

Thanks all for this suggestion. It is being taken under consideration.

To follow up here I want to point out that for the actual survey, there will be visit tables, and that they do exist for DP0.2 (browse the schema for the Visit or CcdVisit tables).

It is my understanding after talking with the DP0.3 creator team that Visit tables might be included if there is, in the future, an update to the DP0.3 data products to address known issues with DP0.3. However, whether or not the resources exist for such a big update (a new data release), and the timescale for deciding that, is unknown.

Thus, a more practical alternative might be for the DP0.3 creator team to provide a parquet table of the visit coordinates and filters, which could be put in a scratch space and be accessible by all RSP/DP0 users?

Thanks, Melissa. It would also be really helpful to know what the schema of the Visits table or equivalent will be officially in the DPDD. It currently states “It will also contain exposure and visit metadata, SSP-specific tables, etc. These are either standard/uncon- troversial, implementation-dependent, or less directly relevant for science and therefore not discussed in this document.” If the Visits database in DP0.2 is very different from what’s going to be available in DR1, it would be good to know that.

Thanks,
~Meg

I think the Visit and CcdVisit tables for DP0.2 are good representatives of what will exist in the future, yes. Improvements will of course be made where possible, but I don’t think they would become “very” different in terms of basic content and schema.