On Mon, Nov 4, 2013 at 7:27 AM, Enzo Cocca <enzo....@gmail.com> wrote: > yes barry I really need this. > > I tried to use raster or rgdal but with poor results. > > I have this function: > > VGM_PARAM_A3 <- gstat(id="bos_bison", > formula=combusto~1,locations=~coord_x+coord_y, data=archezoology_table, > nmax = 10) > > VGM_PARAM_A3 <- gstat(VGM_PARAM_A3, model=vgm(1, "Sph", 5, 0), > fill.all=TRUE) > > ESV_A3 <- variogram(VGM_PARAM_A3, map=True, with=0.1, cutoff=9) > > VARMODEL_A3 = fit.lmc(ESV_A3, VGM_PARAM_A3) > > plot(ESV_A3, threshold = 5, col.regions = bpy.colors(), xlab=, ylab=, > main="Map - A3") > png("C:\Users\User\pyarchinit_R_folder\A3 semivariogram_map.png", > width=10000, height=10000, res=400) > > I make a png file but how can I convert it in ascii-grid?
Why do you want to make an ascii-grid out of this? The variogram map isn't in geographical coordinates, its in coordinate differences in x and y The return value when map=TRUE doesn't seem to be too well documented, but looks like it is a list with a 'map' element that is a spatial pixels data frame. Here's an example using the demo data (I can't run your code because I don't have your data, please try and make your problems easily reproducible): require(sp) require(gstat) data(meuse) coordinates(meuse)=~x+y v=variogram(log(zinc)~1, meuse,map=TRUE,cutoff=900,width=10) class(v$map) [1] "SpatialPixelsDataFrame" attr(,"package") [1] "sp" Now that can be written using rgdal's writeGDAL function. However, you need the AAIGrid driver to work properly: > writeGDAL(v$map,"vmap.ag",driver="AAIGrid") Error in .local(.Object, ...) : Dataset copy failed raster package to the rescue: > require(raster) > writeRaster(raster(v$map),"v.asc","ascii") class : RasterLayer [etc] When I look at the file, I have an ESRI grid file: $ head -5 v.asc NCOLS 181 NROWS 181 XLLCORNER -905 YLLCORNER -905 CELLSIZE 10 [+ data] Now, that's assuming you wanted to write the data, not a pretty image picture like you get when you plot the variogram map. And there's still the mystery of why you want to write a non-geographic coordinate-based dataset to a geographic data format... And you should probably have asked this on R-sig-geo where the geographRs (including the authors of gstat) hang out. Hope this helps anyway. Barry ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.