Here is alternative (non-computational) approach to ensure that the files are read as signed integers:
library(raster) bio <- raster("bio1_23.bil", native=T) dataType(bio) <- 'INT2S' NAvalue(bio) <- -9999 plot(bio) Robert On Fri, Oct 15, 2010 at 4:10 AM, Jaime R. Garcia Marquez <jaime.gar...@uni-bonn.de> wrote: > Hola Manuel, > > Regarding the values of the .bil files I was dealing with that also sometime > ago. > > I found this link in a forum who helped me understand what is going on with > these files: > > http://pvanb.wordpress.com/2010/02/06/importing-worldclim-climate-bil-datalayers-in-grass-gis/ > > So I wrote in R something like this to get the right values: > > library(raster) > bio <- raster("bio1_23.bil") > ind <- which(bio[] > 32767) > bio[ind] <- bio[ind] - (65535+1) > bio[bio[] == -9999] <- NA > bio > plot(bio) > > Hope this helps. > > Saludos, pura vida > > Jaime > > On Thu, 14 Oct 2010 16:17:25 -0600 > Manuel Spínola <mspinol...@gmail.com> wrote: >> >> Thank you very much Robert, >> >> Now I have this error: >> >> > me <- maxent(bio1res, arb) >> Error en .local(x, p, ...) : >> more than half of the presence points have NA predictor values >> >> It could be related to the raster "bio1res"? The origin of this file is >> .bil files. Which is the best file format to work with bioclim data? >> The plot(bio1res) display with a legend with values from 0 to 50000 and >> the raster is for temperature. >> >> bio1res >> class : RasterLayer >> filename : >> nrow : 382 >> ncol : 407 >> ncell : 155474 >> min value : 47 >> max value : 55537 >> projection : NA >> xmin : -85.95 >> xmax : -82.55833 >> ymin : 8.041667 >> ymax : 11.225 >> xres : 0.008333333 >> yres : 0.008333333 >> >> Best, >> >> Manuel >> >> >> On 14/10/2010 02:44 p.m., Robert J. Hijmans wrote: >>> >>> I think it should be: >>> >>> res<- mask(bio1cr, crmask) >>> >>> On Thu, Oct 14, 2010 at 1:22 PM, Manuel Spínola<mspinol...@gmail.com> >>> wrote: >>>> >>>> Dear list members, >>>> >>>> I am working with bioclim variables to model species distribution. >>>> The files downloaded from Worldclim.org are generic raster files (.bil) >>>> I transform this files to raster: >>>> >>>> bio1<- raster("bio1_23.bil") >>>> >>>> cr = readOGR(dsn="C:/ProyectoRespacial/EvalHab_reporte", >>>> layer="Cr_wgs84_meso") >>>> >>>> bio1cr<- crop(bio1, cr) >>>> crmask<- polygonsToRaster(cr, bio1cr) >>>> res<- mask(bio1, crmask) >>>> Error en compare(x, mask) : Different bounding box >>>> >>>> plot(bio1cr) the scale legend shows numbers from 0 to 55000 >>>> >>>> Best, >>>> >>>> Manuel >>>> >>>> >>>> -- >>>> *Manuel Spínola, Ph.D.* >>>> Instituto Internacional en Conservación y Manejo de Vida Silvestre >>>> Universidad Nacional >>>> Apartado 1350-3000 >>>> Heredia >>>> COSTA RICA >>>> mspin...@una.ac.cr >>>> mspinol...@gmail.com >>>> Teléfono: (506) 2277-3598 >>>> Fax: (506) 2237-7036 >>>> Personal website: Lobito de río >>>> <https://sites.google.com/site/lobitoderio/> >>>> Institutional website: ICOMVIS<http://www.icomvis.una.ac.cr/> >>>> >>>> [[alternative HTML version deleted]] >>>> >>>> >>>> _______________________________________________ >>>> R-sig-Geo mailing list >>>> R-sig-Geo@stat.math.ethz.ch >>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo >>>> >>>> >> >> >> -- >> *Manuel Spínola, Ph.D.* >> Instituto Internacional en Conservación y Manejo de Vida Silvestre >> Universidad Nacional >> Apartado 1350-3000 >> Heredia >> COSTA RICA >> mspin...@una.ac.cr >> mspinol...@gmail.com >> Teléfono: (506) 2277-3598 >> Fax: (506) 2237-7036 >> Personal website: Lobito de río >> <https://sites.google.com/site/lobitoderio/> >> Institutional website: ICOMVIS <http://www.icomvis.una.ac.cr/> >> >> [[alternative HTML version deleted]] >> > > > > _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo