TagAvg (Tag-based PE function)

Find the time-weighted average value of a point over a given time, according to values stored in the PI Archive.

Syntax

TagAvg(tagname, starttime, endtime [, pctgood])

Arguments

tagname

A tagname. This point must represent a continuous variable.

starttime

Must be a time expression representing the beginning of the time range to search.

endtime

Must be a time expression, greater than starttime; representing the end of the time range to search.

pctgood

Optional. Minimum time percentage over the given time range, that the point's archived values must be good.

Returns

The point's time-weighted average value over the given time.

Exceptions

If the point has no good values or the pctgood minimum is not reached for the given time range, returns an error value.

Notes

Note: If the point has few good Archive values during the time period, this function's result may not be trustworthy. Use the PctGood function to find out what percentage of the values are good.

Example

TagAvg('tag1', 'y', '*')

TagAvg('tag1', '14-Dec-97', '+1d',70)

TagAvg('tag1', '14-Dec-97', '15-Dec-97')