Isaque, If your LandScan raster is at 30m resolution, then best might be to `aggregate()` to as close as 250m (e.g. using `fact=8` or `fact=9` and `fun=modal`), and then use `projectRaster()`:
projectRaster(from, to, method="bilinear") Others might have better ideas. --Mel. On 8/26/2016 10:43 PM, Tom Philippi wrote: > Mel's answer is complete if you are aggregating to an integer multiple > of grid cells: if your tree cover was 5, 10, 25, 50, 125, etc., m > pixels. If you are unlucky enough to have your tree cover in 15 or > 30m pixels, you may need to disaggregate to greatest common factor (5 > or 10m) cells first, then aggregate up to 250m MODIS. With mode on > categorical data, that should still give you your expected results; > with continuous raster values and other functions, it might not be > appropriate. > > Tom 2 > > > On Fri, Aug 26, 2016 at 7:28 PM, Bacou, Melanie <m...@mbacou.com > <mailto:m...@mbacou.com>> wrote: > > Isaque, check this thread on StackExchange: > > http://gis.stackexchange.com/questions/177423/r-aggregate-raster-with-mode-function-how-does-it-work > > <http://gis.stackexchange.com/questions/177423/r-aggregate-raster-with-mode-function-how-does-it-work> > > --Mel. > > > On 8/26/2016 10:07 PM, Isaque Daniel wrote: > > Hi dear all, > > > > > > I need to resample a tree cover map create by Landsat imagery to > the MODIS 250 meters. > > > > If I use the resample function of raster package, it will > compute the value based on bilinear or ngb, in this condition the > new class map will not answer my expectations. > > > > > > I loking for a way of resample using the statistical mode to > define the value of the pixel of the new map. > > > > > > Some tip about this? > > > > Thanks > > Isaque > > > > > > > > > > ------------------------------------------------------------------------------------------------------------------ > > Agronomist engineer > > Master in Remote Sensing - National Institute for Space > Research (INPE) - Brazil > > PHD Student in Transport - Bras�lia University (UNB) > > > > [[alternative HTML version deleted]] > > > > > > > > _______________________________________________ > > R-sig-Geo mailing list > > R-sig-Geo@r-project.org <mailto:R-sig-Geo@r-project.org> > > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > <https://stat.ethz.ch/mailman/listinfo/r-sig-geo> > > > [[alternative HTML version deleted]] > > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@r-project.org <mailto:R-sig-Geo@r-project.org> > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > <https://stat.ethz.ch/mailman/listinfo/r-sig-geo> > > [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo