Metrics that utilize multiple attributes

[rrowlands]

It would be really nice to know how to utilize other attributes within a particular metric. For example:

I need a metric which first filters based on points where the pixel includes at least one classification with a value of 5 (otherwise set value to zero). OK, now, with that filtered, then I want to do max minus min for the Z attribute.

I think this is possible just reading through some of these pre-defined metrics here:
https://github.com/hobuinc/silvimetric/tree/main/src/silvimetric/resources/metrics

Although to be honest I'm not entirely sure. Maybe this is only possible in the silvimetric core but not in user defined metrics?

If its possible some documentation on how to use it would be nice. Otherwise I guess this could be considered as a feature request.

[kylemann16]

Currently SilviMetric uses dataframe.groupby.aggregate (docs here) to perform Metric functions. Aggregate applies a function over a column of data, and in order to use data from other attributes, we would need to pass it in as an argument here. So in its current form, Metrics cannot reference an Attribute that it is not currently working on.

I don't think this would be a big thing to implement, but I haven't researched it too much yet.