integrate zonal with OnlineStats

[asinghvi17]

https://github.com/joshday/OnlineStats.jl

deepcopy works on any online stat, so we can deepcopy the passed in stats and then fit! into them as part of the zonal. This can be in a package extension.

Interest?

[asinghvi17]

This would enable e.g zonal(Series(KahanSum(), Variance(), ExpandingHist(500)), raster; of = geoms).

[asinghvi17]

But also the ability to do running means, etc. Not sure if this is a great idea, but thought I'd put it up for discussion.

[felixcremer]

You might want to look at the integration of online stats into YAXArrays. There it is not used for zonal, but for table aggregation.

[rafaqz]

Would be cool to integrate diskarrays chunks, is that what you mean?

[asinghvi17]

More that we could do zonal(OnlineStats.KahanSum(), ras; of = geoms) and have it return one of:

• value(stat): a number
• stat: an OnlineStats object

Not sure which is more valuable / sensible. But it would potentially allow us to be completely lazy and avoid materializing anything. Maybe that's the way to go...