Average_Sampled()

Format

Average_Sampled(Expr ,StartTime [,EndTime])

Note: This function was named Hist_Average in v2.6.

Returns

Returns the average of the values of an expression over a range of time.

Inputs

Expr: The expression whose values should be averaged.
Behaviour: Required
Dimension: Collection
Valid data types: Boolean, Decimal, Duration, Integer

StartTime: The start time over which to produce the average. You can use the Time() function to use a valid DateTime argument.
Behaviour: Required
Dimension: Collection, SingleValue
Valid data types: DateTime, Decimal, Integer, String

EndTime: The end time over which to produce the average. If not specified, it assumes the current time. You can use the Time() function to use a valid DateTime argument.
Behaviour: Optional 
Dimension: Collection, SingleValue
Valid data types: DateTime, Decimal, Integer, String

How to format data types

When to Use

This is a sample-based average, that is, it sums all of the values in the time range, and then divides by the total number of samples. This is most appropriate when producing averages of a batch-based quantity, such as the moisture content of coal shipments.

It is possible to retrieve very large volumes of data through indiscriminate use of this function. Retrieving large amounts of Historian data across a slow network can affect system performance for all users of the system.

Examples

Expression: Average_Sampled(Expr, Time() - 60, Time())
Result: Average over the last minute (60 seconds).

Expression: Average_Sampled(Expr, Time() - 60)
Result: Average over the last minute (60 seconds).

Expression: Average_Sampled(Expr, Midnight(Time()))
Result: Average since midnight (the start of the day).

Expression: Average_Sampled({tag, sampleMethod = "Raw"}, Time() – 60)
Result: Average of the raw values over the last minute.

Expression: Average_Sampled(Sampling(Expr, "raw"), Time() - 60)
Result: Average of the raw values over the last minute.