How the Symphonie logger averages vane channels...

The important thing to know is that the averaging for wind vanes is a unit vector"average. That is, it weights all samples equally. In other words, its a time average of the direction unit vectors. On our wind vanes, signal increases from East of North through midrange at South, to its highest value at West of North. We do a linear average on non-vane channels by accumulating the sum of the samples during the interval, then dividing by the number of samples, of course. On a wind vane, there is a pathological case where there are a number of samples East of North and a number West of north. This gives a linear average around South, and the correct value is its mirror image. The NRG logger algorithm handles the case to give the correct mirrored result. The exact algorithm is considered a trade secret, but that's the general idea.