Dear all, I tryed both suggestions and they worked fine. In fact, the short solution is
require(rgdal) require(maptools) mes01jan<-readGDAL("jan_00") write.asciigrid(mes01jan,"mes01jan.asc") Thanks Mike! Thanks Alex! best wishes, miltinho astronauta brazil On Fri, Sep 19, 2008 at 10:46 PM, Michael Sumner <[EMAIL PROTECTED]>wrote: > I tried this, and AAIGrid is not available for creation by rgdal on my > machine. See gdalDrivers() for those available. > > If you install FWTools you can use a workaround to convert the export > externally, e.g. > > x <- readGDAL(system.file("external/test.ag", package="sp")[1]) > > ## write to GeoTIFF > writeGDAL(x, "mes01jan.tif", type = "Byte") > > ## convert externally to AAIGrid > system("gdal_translate mes01jan.tif mes01jan.asc -of AAIGrid -ot Byte") > > ## check result > system("gdalinfo mes01jan.asc") > > I don't believe that AAIGrid can explicitly support type Byte without > augmentation, so I would carefully check the coercion that occurs (if it's > actually needed). > > Cheers, Mike. > > milton ruser wrote: > >> Dear all, >> I am reading a set of maps from ArcGRID format using rgdal and I need to >> export to ASC format. >> >> But when I try the commands below, I get an error. >> >> require(rgdal) >> >> mes01jan<-readGDAL("jan_00") >> image(mes01jan, col=topo.colors(50)) #looks find >> writeGDAL(mes01jan, "mes01jan.asc", drivername = "AAIGrid", type="Byte") >> >> Any idea? >> >> miltinho, brazil >> >> [[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 >> ------------------------------------------------------------------------ >> >> >> No virus found in this incoming message. >> Checked by AVG - http://www.avg.com Version: 8.0.169 / Virus Database: >> 270.7.0/1681 - Release Date: 9/19/2008 3:54 PM >> >> >> > > [[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