Should the multiscale tools produce multiple outputs?

[DOSull]

When we tried (in the R package)

wbt_multiscale_roughness(..., max_scale = 10, min_scale = 1, ...)

we were a bit surprised not to get multiple output files, or perhaps a multi-band output raster. Instead, we just get one output, which seems to be the max_scale result, or possibly, inferring from the description of multiscale_curvature the single output is some kind of combination of the results of running the roughness calculation at various scales?

It's clear from the console messages that the calculation is running at multiple scales, it's just not obvious where all the results are ending up!

Obviously, it's not hard to set up your own loop, and iterate with max_scale = min_scale = scale where scale is the loop iterator, I just wonder if this is the expected behaviour? If so, it would be good if the documentation made this clearer. If not, then I guess this is a bug report!

[jblindsay]

Each of the multiscale land-surface parameter (LSP) tools output scale-mosaics, i.e., the measure of the LSP for a particular pixel in the output raster is some kind of scaled optimum, e.g., the maximum absolute value of the LSP measured across a range of scales. If you would like to create multiple scaled outputs, simply run the tools multiple times using single scale parameter inputs, rather than scale ranges. I agree that in the case of the MultiscaleRoughness tool, the documentation should be much clearer, although, most of the other multiscale tools are actually quite clear on this, I think. I will work on improving the MultiscaleRoughness documentation. Most of the tools also output not a single raster, but two rasters, where the first raster is the scale mosaic and the second raster is the scale value (i.e., the scale at which the optimum LSP value was identified).

[DOSull]

OK. Thanks for the clarification - the help information could certainly be a bit more explicit about what the outputs are.

Perhaps also worth knowing (if you didn't already!) that on inspection of a scale output when I set max_scale = 5 and min_scale = 1 that the numerical range in that output is from 1 to 4 only, so this tool may be non-inclusive over the specified scale-range, similar to the concern raised in #107.

Correction I checked with a different scale range, and apparently it is doing inclusive range. Ignore the reference to a previous issue above.