Calculated meters
Calculated meters calculate their values from their input meter values. These values can be calculated using three different formulas: SUM, DIFF or CUSTOM.
Key rules
- Calculated meters ONLY handle events after lock date on the calculated meter. All events before lock date are omitted. Relevant values on the input meters before their lock date are included, but only ever read and never modified in any way.
- To be able to run the formula and store a meter value for the calculated meter, ALL inputs for the given timestamp and resolution MUST have a value. The function MUST return a scalar value. If these conditions are true, the calculated value is stored.
- All calculated values overwrite any potentially existing value for that time and resolution.
- Deleting a value on a input meter causes the calculated value to be deleted as well.
- On formula error, all calculated values for that meter will be set to 0.
(Re)calculation
Calculated meter values are (re)calculated whenever any of the following occurs:
- Any input changes
- Input sort order changes
- Any input value changes
- Formula changes
- Lock date for the calculated meter changes
- Factor of the meter changes
- Factor of an input changes
While the meter is calculating any of it's values, the status indicator for the meter is orange. Once the meter has finished all calculations, the indicator becomes green.
