I want to convert a raster map encoding directional flows (the output of
r.terraflow) to a vector map. I'm using
r.thin to process the output. It terminates successfully with 0 pixels removed during the last iteration. Yet when I try to vectorise the result with
feature=line, I get the following error message:
Extracting lines... ERROR: Raster map is not thinned properly. Please run r.thin.
I have tried rerunning
r.thin on the already thinned output, with the same result. I did not find anything in the documentation of either
r.to.vect to suggest what might be the problem here or how to fix it.