
Re: Standard Deviation Calculation
tramachandran Sep 2, 2018 11:56 PM (in response to NicPickering)6 of 6 people found this helpfulStdDev is the standard deviation over the time range given by
SStDev returns the sample standard deviation.The sample standard deviation of a sample x1, ... xn is equal to
SStDev(x1, x2 [, ... xn]) in PI Analytics takes arguments x1, ... xn
Arguments and a single array of same value type (integers and real numbers, time expressions, or time intervals)
About entering values, if you have PI AF 2018+ this becomes easy by invoking RecordedValues or other array functions as an input.
If this is a oneoff calculation you could you AF Explorer, right click on the attribute, Time Series
This can be programmatically achieved in AF SDK through PIPoint.Summaries method and specifying AFCalculationBasis as PopulationStdDev

Re: Standard Deviation Calculation
NicPickering Sep 3, 2018 12:32 AM (in response to tramachandran)Thank you very much for your reply.
Unfortunately I am using an older version of PI and I do not have access to the "recordedvalues" performance equation.Thanks for clearing up which formula is used in the two different equations though!

Re: Standard Deviation Calculation
tramachandran Sep 3, 2018 3:14 AM (in response to NicPickering)1 of 1 people found this helpfulAlso you can try this utility PI DataPipe Events Subscription and Data Access Utility using AF SDK  PIEventsNovo
You get the different summary/summaries calculations(event or time based) of one or more tags as follows without the need to write your own program in AF SDK.

Re: Standard Deviation Calculation
NicPickering Sep 4, 2018 5:52 AM (in response to tramachandran)That is literally everything I need. You are a life saver! Thank you so much!
<3 <3 <3


