On 1/7/2011 12:40 PM, Jon Olav Skoien wrote:
Pearl,

The error suggests that there is something wrong with x2, and that there is a difference between the row names of the coordinates and the data. If you call
str(x2)
see if the first element of @coords is different from NULL, as this can cause some problems when cross-validating. If it is, try to figure out why. You can also set the row.names equal to NULL directly:
row.names(x...@coords) = NULL
although I dont think such manipulation of the slots of an object is usually recommended.

Pearl,

It seems the problem was caused by a recent change in sp without updating gstat, the maintainer has fixed it and submitted new version of gstat to CRAN. So you should be able to use your original script after downloading the new version, probably available in a couple of days. In the mean time the suggestion above should still work.

Cheers,
Jon


Cheers,
Jon

BTW, you will usually get more response to questions about spatial data handling using the list r-sig-geo (https://stat.ethz.ch/mailman/listinfo/r-sig-geo)


On 1/6/2011 4:00 PM, pearl may dela cruz wrote:
ear ALL,

The last part of my thesis analysis is the cross validation. Right now I am having difficulty using the cross validation of gstat. Below are my commands
with the tsport_ace as the variable:

nfold<- 3
part<- sample(1:nfold, 69, replace = TRUE)
sel<- (part != 1)
m.model<- x2[sel, ]
m.valid<- x2[-sel, ]
t<- fit.variogram(v,vgm(0.0437, "Exp", 26, 0))
cv69<- krige.cv(tsport_ace ~ 1, x2, t, nfold = nrow(x2))

The last line gives an error saying:
Error in SpatialPointsDataFrame(coordinates(data),
data.frame(matrix(as.numeric(NA),  :
   row.names of data and coords do not match

I don't know what is wrong. The x2 data is a SpatialPointsdataframe that is why i did not specify the location (as it will take it from the data). Here is the
usage of the function krige.cv:

krige.cv(formula, locations, data, model = NULL, beta = NULL, nmax = Inf, nmin = 0, maxdist = Inf, nfold = nrow(data), verbose = TRUE, ...)
I hope you can help me on this. Thanks a lot.
Best regards,
Pearl




    [[alternative HTML version deleted]]

______________________________________________
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.

______________________________________________
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.

______________________________________________
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.

Reply via email to