Since years I'm using VB.NET make graphs and tables from vaules in PI. So far I have always used PIOLEDB to connect to PI and fetch the values. Using a SQL something like:
SELECT value from piarchive..piavg WHERE tag= 'Test-Value' AND time BETWEEN '01-12-2011' AND '01-01-2012' AND timestep= '1m' AND calcbasis='TimeWeighted'
I'm now wondering if I can upgrade my code to use AFSDK. Maybe i'ts faster or at least more modern. :-) Reading the documentation I'm a bit confused. I have tried several snippets but none are giving me the desired effect. Basically I want a function giving me a array (or list or something) with the values over a given timeframe averaged in the fragments I want. Like two days of data,1 minute averages giving 1440 X 2 = 2880 values. The closed I came is interpolated values but this is just not good enough. Can someone point me in the correct direction or does someone has a code sample? I looked read hard on the net but found nothing.