Points / Rating Assign List
Introduction
A rating is a value returned from a computation table that is stored in a data report. For example a water level data report value in feet can be used to compute the stream discharge in cubic feet per second. NovaStar supports up to five different rating values stored in the data report. Rating tables (see the Rating Table List section) are assigned to a point to compute the rating values. Different rating tables can be assigned for use at different time periods. Rating shifts can also be added to a rating assignment to adjust a rating rather than add a new rating table. As with rating tables, different rating shifts assigned for use at different time periods. When ratings are active for a point, the assigned rating values are computed and stored in the data report when the data report is filed in the database.
Clicking on the Points / Rating Assign List menu displays the Rating Assign List page. A new NovaStar system will display an empty Rating Assign List. The following image illustrates the Points / Rating Assign List page after a rating has been selected in the list at the top of the page.
Rating Assign Page (see full-size image)
Rating Assign List
The full list of ratings are displayed at the top of the page.
Rating Assign List (see full-size image)
Navigation, Adding, Deleting, Modifying, and Copying Rating Assigns
See Application Functionality for more information about basic component functionality.
The Rating Assign List page conforms to a layout similar to many data types which includes a list of data items. See List Features for more information detailing page navigation; adding, copying and deleting rating assigns; and modifying existing rating assigns.
Identification
The following properties are used to identify the rating assign.
Rating Assign Identification (see full-size image)
| Data Label | Description |
|---|---|
| Point: | Select a point for calibration from the pick list. |
| Open | Select point for table open value from the pick list. |
| Computation | Rating table computation direction.
|
| Number | Rating number for this assignment. A point can have up to 5 rating assignments. Each rating assignment can have different rating tables assigned. |
| Name | Rating assignment name is required but does not have to be unique. It should describe the rating table and shift use. If multiple rating assignments are created for a point over different time periods, add a time designator to the name. Max: 100 characters. |
| Table | Select rating table for rating assignment from the pick list (only shown when applicable). Click the  button to edit the Rating Table. |
| Effective time | Date and time when rating assignment becomes effective. Point ratings can change over time due to channel profile changes. NovaStar keeps a time history of point rating assignments in the data base. A point rating assignment remains in effect from the effective time forward until another rating assignment is added with a newer effective time. The  button assigns the current date and time. |
Rating Shifts
The Rating shifts list the shifts assigned to the rating table. When a rating assignment is first defined, no rating shift records will be assigned.
Changes in a river channel profile necessitate modifying the rating table. If the change only affects part of the profile then adding shifts to the rating table rather than creating a new table is more efficient. A rating shift record contains the shift type, point index data value where the shift starts, the shift value added to the point index data value, and an optional time interval for prorating the shift over time. The rules for computing a shift value for a point index data value are as follows:
- Data values that match a shift row index use the shift value for that row.
- Data values between two shift row indices use an interpolation between two shift row values.
- Data values less than the first shift row index use the shift value for the first shift row.
- Data values greater than the last shift row index use the shift value for the last shift row.
Rating Assign Shift List (see full-size image)
| Data Label | Description |
|---|---|
| Type | Type of shift.
|
| Index | Index data value for start of shift. |
| Value | Shift value added to index data value. |
| Interval | Prorate start of shift over this interval. Default: none. |
Rating Recomputation
When a rating table is assigned to a point and ratings are enabled then rating values are automatically computed and stored in the data report for incoming data streams. If a rating assignment changes for data reports already stored in the database then the rating values must be recomputed using this tool.
Hovering over the 
displays the command that will be run upon clicking button.
Rating Assign Rating Computation (see full-size image)
| Data Label | Description |
|---|---|
| Starting Time | Select the starting time for the rating computation. Click  to set the starting time to the rating assignment effective time. Note: the starting time must before the ending time. |
| Ending Time | Select the ending time for the recalibration. |
| Quiet | false prints the command activity in the display window; true only prints the command start and stop messages. Use true for the fastest command performance. |
| Digits | Select the number of decimal digits to display, leaving unselected uses point type assignment. |
Rating Assign Delete
To delete a rating assign from the Rating Assign List, select the rating assignment, click Edit and then click Delete. The page prompts again with a popup to confirm the deletion. Deleting the rating assignment will not remove rating values already computed and stored in the point data reports.