Ivan Shmakov wrote: > > Is there some fundamental reason why r.univar has separate cases for > > CELL/FCELL/DCELL types, rather than just working in DCELL throughout? > > > Most of the time, there's no value to having separate CELL/FCELL > > cases. There's hardly ever a reason to have a separate FCELL case, > > and a separate CELL case is only really useful if you specifically > > need integer-specific operations (e.g. integer division, bitwise > > operations etc). > > > I'm aware that r.univar was already like this, but if there isn't a > > valid reason, this would be a good time to simplify it. > > I don't know for sure, but apparently the distinction is only > effective when gathering extended statistics (percentiles, > median.) > > Since the extended statistics code temporarily stores all the > values from the raster(s) being processed, using native types > may lead to reduced memory usage and processing time.
I doubt that it will make much difference regarding overall processing time. So far as memory usage is concerned: if we think that people might want to compute quantiles on data sets which are large enough that we need to worry about memory consumption, we should probably be looking for a more efficient algorithm. Sorting the entire data set then pulling out quantiles is less than ideal if you're dealing with that much data. -- Glynn Clements <[EMAIL PROTECTED]> _______________________________________________ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
