Please consider using the R-sig-geo list for kriging questions. In fact, using str() would show that your z is badly impacted by your misuse of the c() function - this was almost certainly not what you wanted to do.
Constructing your coordinates by using seq() is always a bad idea, as you need to be very careful in assigning position to data. Start by making sure that your (long, lat) matrix of coordinates is correctly associated with the data (you speak of a matrix with missing values - think of it as a vector, or use an sp function to convert from "image" format to a SpatialGridDataFrame, and coerce to a SpatialPixelsDataFrame). In fact, if your data are on a grid, it is more than puzzling for what purpose you want to use kriging interpolation, unless to hope to change resolution, or fill in the missing values. You need to think much more carefully about your data representations. Those used in the gstat package were chosen to avoid slip-ups with input data (and output data), and use by default classes defined in the sp package. Have you consulted the "Spatial" task view on CRAN? Hope this helps, Roger karine heerah wrote: > > > Hi everybody, > > > > I have a longitude vector and a latitude one. Associated to these > coordinates, i have a matrix with some data at some coordinates but not > all. > > > > Lon <- seq(136.025,144.975,0.05) > Lat <- rev(seq(-66.975,-65.525,0.05)) > > > > dim(z) <- c(Lon,Lat) > > > > And i have tried to apply to these data a kriging function. But first i > need to reshape these 3 variables to have a dataframe with these and with > the corresponding z values with the good coordinates. Do you know how i > can do that? > > > > And i will have the same problem with the object that return the krige > function (gstat package). It gives me a dataframe, and i want a matrix for > the prediction. How can i do that, in order to plot it with the image > function after. > > > > Thanks a lot > > Karine HEERAH > > Master 2 , océanographie et environnements marins > Université Pierre et Marie Curie (Paris 6) > 42 rue Salvador Allende > 92000 Nanterre > 06.61.50.97.47 > > > > > > _________________________________________________________________ > [[elided Hotmail spam]] > tre téléphone! > > [[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. > > ----- Roger Bivand Economic Geography Section Department of Economics Norwegian School of Economics and Business Administration Helleveien 30 N-5045 Bergen, Norway -- View this message in context: http://n4.nabble.com/kriging-problem-very-urgent-tp1754267p1773886.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
