On Wed, Nov 2, 2016 at 5:15 PM, Markus Metz <[email protected]> wrote: > On Wed, Nov 2, 2016 at 3:47 PM, Moritz Lennert > <[email protected]> wrote: >> On 02/11/16 11:05, James Duffy wrote: >>> >>> I can't register with osgeo to submit a bug as no-one has replied with a >>> 'mantra' for me to do so... what a convoluted bug reporting system! >>> >>> And in your opinion Moritz, does it look like my workflow will not be >>> possible unless I find a 64bit machine with a decent amount of RAM? >> >> >> I'm not sure about the necessity of 64bit, but more RAM probably. >> >> IIUC, all the stats of all the zones are put into memory during the run of >> the module. Maybe a file-based store of the information might be possible >> which would avoid this memory usage, but I'm not sure. >> >> @MarkusM: could you have a look at this ? See >> https://lists.osgeo.org/pipermail/grass-user/2016-October/075493.html for >> the beginning of the thread. In short: James seems to be hitting memory >> limits of r.univar and I'm wondering out loud whether there is something >> that could be done about this... > > As Anna wrote, the -e flag increases memory consumption of r.univar > considerably. A file based approach for extended stats of r.univar is > difficult because the number of values per segment is initially > unknown to r.univar, thus the amount of disk space needed for extended > stats for each segment is unknown. > > I would rather use r.univar for standard stats and r.stats.quantile > for extended stats.
There were some bugs in r.stats.quantile, fixed in r69770-2 in all G7 branches. About the limit to MAX_CATS categories in the base map (ticket #3198), there is not really a reason for it. I guess it is meant to protect against out-of-memory errors. Markus M > The options for raster_statistics of > i.segment.stats would then reduce to "min, max, range, mean, > mean_of_abs, stddev, variance, coeff_var, sum, sum_abs", and a new > option, e.g. raster_percentiles could be added, accepting a list of > percentiles which can be directly fed by i.segment.stats to > r.stats.quantile percentiles=<list of percentiles>. > > Markus M _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
