Hello,

 My name is Matthew Sokol and I am using the package geoR and I am having a 
little trouble using the "grf" function.

 What I am trying to do is to simulate data that follows the same variogram 
model as a certain data set. 

 So I start with the built in data set s100.

 It says that it has a Sill equal to one and a range equal to .3 based on 
the following commands:

 plot(variog(s100,max.dist=1))

lines.variomodel(cov.model = "exp", cov.pars = c(1, 0.3),nug = 0,max.dist=1)

loci <- expand.grid(seq(0,1,l=21), seq(0,1,l=21))

kc <- krige.conv(s100, loc=loci,krige=krige.control(cov.pars=c(1, .3)))

image(kc)

 Now what I want to do is to simulate data on the same grid that follows the 
same variogram model. So I run the following commands:

 sims100 <- grf(100, ylims=c(0,0), cov.pars=c(1,.3), nugget = 0, cov.model=
"exp")

simkc <- krige.conv(sims100, loc=loci,krige=krige.control(cov.pars=c(1, 
.3))) 

image(simkc)

 But when you compare the two images of 'kc' and 'simkc' they are nothing 
alike. 

 What I am ultimately trying to do is create a new data set within my 
original location that accurately reflects the original data. Then I would 
like to resample the data to see how different sampling locations affect OK 
and OK stand deviation. 

 Would re-sampling from the data set 'kc' be ok here since the
krige.convcommand creates a new data set based off the original model
at new locations
( i.e. the location "loci").  

 I am not sure if I am running the commands wrong or if I am using the 
functions totally wrong. I am a novice at best when it comes to using R, and 
I hope anyone can point me in the right direction. 

 Thanks in advance for any help.

 -Matthew Sokol

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