Sliding window calc

Is it possible to do a “sliding window” calc in Sigma? ( a window of specified length moves over the data, sample by sample, and the statistic is computed over the data in the window)

Sounds like you’re looking for Window Functions.
My guess is that MovingAverage will do what you need.

Thanks. So the MovingAverage will account for this?:

If I am understanding your link correctly, it should.
The key to making MovingAverage work the way you intend is to set up the windows correctly. You need to have a unique sort so that the rows are always in the same order. Then, each group defines it’s own window, so MovingAverage will start over at each grouping.