Dear All, I am facing problem to obtain the nested variogram model for the 3D lithological data. I have 3D data, in which the coordinate are x,y,z (z corresponds to the depth) and the lithofacie information for different materials as a binary values (Ind01, Ind02, Ind03, Ind04, Ind05) . Now I would like to develop sequential indicator simulation to obtain the facies distribution for each of the category. I have used gstat to develop the vertical and horizontal varigram but unable to fit as a nested variogram for both vertical and horizontal direction. Is there any one help me to combine the vertical and horizontal variogram in one nested structure. The data I have used from the greengoblin data. A dropbox link has been placed at the end of this post to obtain the data. The code I have used as follows to obtain the vertical and horizontal variogram for the Ind03 facies (medium sand) green_gstat <- as.data.frame(green_goblin) coordinates(green_gstat) = ~X+Y+Z names (green_gstat) class(green_gstat) # vertical variogram ind03_vert <- variogram((Ind03)~X+Y+Z, green_gstat, cutoff = 250, width= 2, alpha= 0, beta = 90) # fitting the variogram model ind03_fit <- fit.variogram (ind03_vert, vgm(1, "Exp", 500,1)) # plotting plot(ind03_vert, ind03_fit) # estimating the horizontal variogram in omni direction Ind03_hori_omni <- variogram(ind03, cutoff = 15000, width = 1000, alpha = 0) # fiting variogram mdoel ind03_fit_dir <- vgm(.188, "Exp", 1500, .05, anis = c (45, .25)) # obtain the fit model informaiotn Ind03_fit_vrio_hor <- fit.variogram(Ind03_hori_omni,vgm(.188, "Exp", 1500, .05, anis = c (45, .25))) # plotting the data plot(Ind03_hori_omni,ind03_fit_dir) # now I have tried to go for the nested variogram approach, typically what I have found there, that one can create the nested model like this from the same variogram, but using diffent fitting options. ind03_vertnested <- fit.variogram (ind03_vert, vgm (1, "Exp", 500, add.to = vgm (.188, "Exp", .05, anis = c(45, 0.25)))) here I have only used the ind03_vert (variogram), but I also have a horizontal variogram model (Ind03_hori_omni). So, how I can incorporate two model into a single variogram model. A feedback in this regard would be highly appreciate. Or, is there any other option to create a 3D variogram modeling. To have the data, please follow this dropbox link for the easy access. Link to the data- https://www.dropbox.com/s/6xl8zh7ofntlna6/GreenGoblin.csv?dl=0 -- A.B.M Firoz ITT- Institute for Technology and Resources Management in the Tropics and Subtropics Technology Arts Sciences T: +49 221 8275-2059 F: +49 221 8275-2736 Kalk- Campus www.tt.fh-koeln.de _______________________________________________ R-sig-Geo mailing list [hidden email] https://stat.ethz.ch/mailman/listinfo/r-sig-geo |
Dear A.B.M.,
fit.variogram will not help you fit directional variograms. In principle, you could write your own optimizer using e.g. stats::optim, and gstat:;variogramLine to compute semivariances give the model for different directions and distances. I'd welcome a pull request with a well-tested function that would make this easy for end users. On 17/05/17 16:04, ABM Firoz wrote: > Dear All, > > > > I am facing problem to obtain the nested variogram model for the 3D > lithological data. I have 3D data, in which the coordinate are x,y,z (z > corresponds to the depth) and the lithofacie information for different > materials as a binary values (Ind01, Ind02, Ind03, Ind04, Ind05) . Now I > would like to develop sequential indicator simulation to obtain the > facies distribution for each of the category. I have used gstat to > develop the vertical and horizontal varigram but unable to fit as a > nested variogram for both vertical and horizontal direction. Is there > any one help me to combine the vertical and horizontal variogram in one > nested structure. > > The data I have used from the greengoblin data. A dropbox link has been > placed at the end of this post to obtain the data. > > > > The code I have used as follows to obtain the vertical and horizontal > variogram for the Ind03 facies (medium sand) > > green_gstat <- as.data.frame(green_goblin) > > coordinates(green_gstat) = ~X+Y+Z > > names (green_gstat) > > class(green_gstat) > > # vertical variogram > > ind03_vert <- variogram((Ind03)~X+Y+Z, green_gstat, cutoff = 250, width= > 2, alpha= 0, beta = 90) > > # fitting the variogram model > > ind03_fit <- fit.variogram (ind03_vert, vgm(1, "Exp", 500,1)) > > # plotting > > plot(ind03_vert, ind03_fit) > > Rplot01 > > # estimating the horizontal variogram in omni direction > > Ind03_hori_omni <- variogram(ind03, cutoff = 15000, width = 1000, alpha = 0) > > # fiting variogram mdoel > > ind03_fit_dir <- vgm(.188, "Exp", 1500, .05, anis = c (45, .25)) > > # obtain the fit model informaiotn > > Ind03_fit_vrio_hor <- fit.variogram(Ind03_hori_omni,vgm(.188, "Exp", > 1500, .05, anis = c (45, .25))) > > # plotting the data > > plot(Ind03_hori_omni,ind03_fit_dir) > > hori > > # now I have tried to go for the nested variogram approach, typically > what I have found there, that one can create the nested model like this > from the same variogram, but using diffent fitting options. > > ind03_vertnested <- fit.variogram (*ind03_vert*, vgm (1, "Exp", 500, > add.to = vgm (.188, "Exp", .05, anis = c(45, 0.25)))) > > here I have only used the ind03_vert (variogram), but I also have a > horizontal variogram model (Ind03_hori_omni). So, how I can incorporate > two model into a single variogram model. A feedback in this regard would > be highly appreciate. Or, is there any other option to create a 3D > variogram modeling. > > > > To have the data, please follow this dropbox link for the easy access. > > > > Link to the data- > https://www.dropbox.com/s/6xl8zh7ofntlna6/GreenGoblin.csv?dl=0 > > > > > > > > > > *--* > > *A.B.M Firoz* > *Researcher- GIS & Hydrological Modeling* > > * * > > *ITT*- Institute for Technology and Resources Management > > in the Tropics and Subtropics > > *Technology* *Arts** **Sciences* > *TH Köln* - University of Applied Sciences > > > > T: +49 221 8275-2059 > > F: +49 221 8275-2736 > E : [hidden email] <mailto:[hidden email]> > > > > Kalk- Campus > RobertStrasse 2 > 51105 Köln Germany** > > www.tt.fh-koeln.de <http://www.tt.fh-koeln.de/> > www.th-koeln.de <http://www.th-koeln.de/> > > > > > > _______________________________________________ > R-sig-Geo mailing list > [hidden email] > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > Edzer Pebesma Institute for Geoinformatics (ifgi), University of Münster Heisenbergstraße 2, 48149 Münster, Germany; +49 251 83 33081 Journal of Statistical Software: http://www.jstatsoft.org/ Computers & Geosciences: http://elsevier.com/locate/cageo/ _______________________________________________ R-sig-Geo mailing list [hidden email] https://stat.ethz.ch/mailman/listinfo/r-sig-geo signature.asc (484 bytes) Download Attachment |
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