Volker Wichmann wrote: > I have upgraded r.in.xyz to allow for the following aggregate > functions: - skewness > - median > - percentile > - trimmed mean > > To make this possible, I created singly linked lists for all points > falling into a cell. I followed a suggestion of Glynn and used arrays > instead of pointers and stored the head of each list in a raster map > ([GRASS-dev] storing pointers in CELL_TYPE maps? (from April 2007)). > The linked lists are then used to calculate the corresponding > statistics before binning the values. > So far we encountered no problems with this approach in our working > group, but I'm not sure about some details. Maybe there should be some > more checks, e.g. to prevent the index to overflow because of too many > cells. > > If you are interested I'd like to share the code. Maybe it would be > best to send a copy to Hamish first?
Hi Volker, cheers for the upgrade, I'm sure it will be useful for many folks. I will be travelling for the next couple of weeks and won't have a chance to look at it before then. In the mean time can you post the unidiff to the code patch tracker? http://wald.intevation.org/tracker/?group_id=21 thanks, Hamish _______________________________________________ grass-dev mailing list [email protected] http://grass.itc.it/mailman/listinfo/grass-dev
