Event-Weighted Summary Functions
Allow for Asset Analytics to support event-weighted summary functions (as opposed to time-weighted), such as average and count. This will allow for easily aggregating changes in digital tags, discrete sensor readings (e.g., bucket count), etc. This would allow Asset Analytics to easily perform many of the event-weighted functions of PI Totalizers.
Event weighted summaries with analysis arrays and event weighted options with some existing functions have been added and release with AF 2018 SP2.
Tom Hosea commented
I believe this request is slated to be included in AF 2018 R2. The original request is: Event-Weighted Summary Functions – User Feedback for OSIsoft Products
Something like Excel's CountIf() would be incredibly helpful. It gets excessive always having to do workarounds or add additional tags to support a calculation. If you don't have an EA, that's not always feasible.
Kenneth Barber commented
The original idea doesn't seem to specifically address Totalizing. Tagtot is a time weighted function. There is not an equivalent event-weighted function . . . this seems like a big gap in capability
Brent Bregenzer commented
This could be applied to any of the standard statistical functions (TagMean, TagMax, etc.). For example a moving average over the last 20 sample values rather over the last 20 minutes.
Kelsey Duffy commented
TagMean does event weighted, but there's no way to get an event weighted total for example. The workaround is to multiply the tagmean by the event count, but even that is not a good workaround because bad values will not affect tagmean but will affect event count, so they need to be handled before the calculation is performed.
Is this not the purpose of the TagMean() function?
TagAvg() will perform a time-weighted average whereas TagMean() should perform an event-weighted average. I haven't verified but this is my assumption.