Questions to cover (from Brian)
1) What "latest" refers to. It's not always possible for to determine the latest rating is.
- Restrict to 'simple ratings'. Algorithm for below threshold; different for above (e.g. backwater in a wier). Potential use for range values. Production vs development data/systems. Return type for cases with multiple conversions, too complex etc. Comes down to how the sites are selected that will be published. Potentially exclude sites that are too complex.
- Conversion service to process a conversion for heights.
- 'Source system' in schema. Return for complex conversions.
- Can you return multiple ratings from a get latest?
- No round tripping of ratings. E.g. identifiers.
2) "Changed since" API calls
What invalidates a rating model? Change in period/table etc. Could result in large computation and/or returns. Either working with current ratings or need to get the whole group again.
3) Parameter vocabulary
Start with WDTF, then extend as appropriate. Start with WDTF spreadsheet.
4) What are the rules for constructing the conversion/rating tables (eg., how many data points should be transmitted). For example, suppose we wanted to exchange a rating that is in the form of an equation, how many points should we use to represent that equation? The RGS item register states: "Ratings should always have a point table supplied that is expanded at a sufficient Y scale resolution to enable linear interpolation between the supplied points. The creator of the data file will choose the export resolution such that linear interpolation is appropriate."
Could provide a parameter in API for stage spacing, with a default across the whole service. Can override with a call from requester. (1/100 ft default for USGS). 5-10mm. Corresponds to accuracy of a gauge reading.
5) Confirm the definition of a conversion group. Is it defined as all the objects (rating tables, rating periods, and shifts) that are used to model the conversion from stage to discharge?
Keyed on site-paramFrom-paramTo.
6) Should calls such as .../rgs-api/v1/conversion/ and .../rgs-api/v1/conversion/C_ID (where C_ID is the conversion ID) return all types of conversions, both ratings and shifts
Yes should contain ratings and shifts. Stage-stage conversion used for purposes other than shifts. Do we need to identify them as shifts? Aus create new tables that incorporate all the changes.
Controlled terms to describe the purpose of the table (e.g. shifts, simple parameter conversion etc.). Starting point? Flow rating, simple/complex (?) conversion (anything else), shift.
7) Review need and implementation of Conversion Period related API calls
Change in period is a change in rating.
8) API syntax. There seem to be a few subtle differences emerging between the implementations, I think (e.g., latest vs id=latest)
Queries on monitoring points: need query by ID and Name at least.
- 30 Apr 2014