Have a look at the examples in the helpfile for variogram from the gstat package.
data(meuse) # no trend: coordinates(meuse) = ~x+y variogram(log(zinc)~1, meuse) # residual variogram w.r.t. a linear trend: variogram(log(zinc)~x+y, meuse) # directional variogram: variogram(log(zinc)~x+y, meuse, alpha=c(0,45,90,135)) # GLS residual variogram: v = variogram(log(zinc)~x+y, meuse) v.fit = fit.variogram(v, vgm(1, "Sph", 700, 1)) v.fit set = list(gls=1) v g = gstat(NULL, "log-zinc", log(zinc)~x+y, meuse, model=v.fit, set = set) variogram(g) if (require(rgdal)) { proj4string(meuse) = CRS("+init=epsg:28992") meuse.ll = spTransform(meuse, CRS("+proj=longlat")) # variogram of unprojected data, using great-circle distances, returning km as units variogram(log(zinc) ~ 1, meuse.ll) } HTH, Thierry ------------------------------------------------------------------------ ---- ir. Thierry Onkelinx Instituut voor natuur- en bosonderzoek / Research Institute for Nature and Forest Cel biometrie, methodologie en kwaliteitszorg / Section biometrics, methodology and quality assurance Gaverstraat 4 9500 Geraardsbergen Belgium tel. + 32 54/436 185 thierry.onkel...@inbo.be www.inbo.be To call in the statistician after the experiment is done may be no more than asking him to perform a post-mortem examination: he may be able to say what the experiment died of. ~ Sir Ronald Aylmer Fisher The plural of anecdote is not data. ~ Roger Brinner The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data. ~ John Tukey -----Oorspronkelijk bericht----- Van: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] Namens giuseppef...@libero.it Verzonden: dinsdag 24 maart 2009 12:45 Aan: r-help@r-project.org Onderwerp: [R] Variogram with Gstat Dear all can you help me? i have this problem: i have a dataset in a text file in a matrix of 3 columns: x, y, z where x and y are the coordinates and Z are the mesurements. How can i do a variogram with R? ______________________________________________ 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. Dit bericht en eventuele bijlagen geven enkel de visie van de schrijver weer en binden het INBO onder geen enkel beding, zolang dit bericht niet bevestigd is door een geldig ondertekend document. The views expressed in this message and any annex are purely those of the writer and may not be regarded as stating an official position of INBO, as long as the message is not confirmed by a duly signed document. ______________________________________________ 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.