dorj

Different results for PrevVal in debug and runmode

Discussion created by dorj on Jun 3, 2010
Latest reply on Jun 8, 2010 by Asle Frantzen

I am writing data to PI with 'out of order' timestamps (as this is laboratory data). I need to calculate the difference between the current input and the previous input. In debug mode everything works ok. In runtime mode however I don't calculate on the new value but on the previous value and the value before that, so the calculation is one step behind.

 

The code looks like:

 

PreValue = InputTag.PrevVal()

 

PreTimeStamp = Inputtag.PrevEvent()

 

PrePreValue = InputTag.PrevVal(PreTimeStamp.UTCSeconds-1)

 

Outputtag.Value(PreTimeStamp) = PreValue - PrePreValue

 

I need the outputtag to have the same timestamp as the inputpoint. If I use Value instead of PrevVal() I don't get the same timestamp as the inputtag,

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