Hi Jessie Zhang, I modified your code and the following works ... it will not be the most elegant solution for sure :) (but I'm not a programmer , just a simply useR).
# this part was ok ######################################################## library(gstat) library(automap) rm(list=ls()) data<-read.csv("sampledata.csv",header=T) pred.basis<-read.csv("bj.csv",header=T) data$date<-as.Date(data$date) day<-unique(data$date) length<-length(day) pred.data<-matrix(NA, nrow = length(pred.basis[,1]), ncol=length, byrow=TRUE, dimnames = list(pred.basis$id,day)) reshape.data<- reshape(data, v.names="pm10", idvar="station", timevar="date", direction="wide") ######################################################### # I first checked and substituted NAs with the means of the data.frame coloumn for(k in 4: 13) { for(i in 1:27) { if (is.na(reshape.data[,k][i])) reshape.data[,k][i]= mean(reshape.data[,k],na.rm=T) } } #explicit data objects coordinates(reshape.data)<- ~x+y coordinates(pred.basis) <- ~x+y # you forgot to do this in your code #I guess there were some problems with the names of the variables, so I decided to use simpler and shorter names without dots names(reshape.data) #check names new_names<- NULL # prepare a vector for storing new names for(i in 1:10) new_names[i] <- paste("z",i, sep="") #create new names names(reshape.data)[-1]<- new_names #assign them to reshape data #for convenience, I decided to eliminate the station col from the reshape.data stations <- reshape.data@data$station #save stations separately reshape.data@data$station <- NULL #erase station coloumn model.auto <- vector("list", 10) #prepare a list for storing the autokrige output for (i in 1:10) model.auto[[i]]<- autoKrige(reshape.data[,i], pred.basis) Cheers Giuseppe Calamita -- View this message in context: http://r-sig-geo.2731867.n2.nabble.com/how-to-choose-best-parameters-of-variogram-model-in-gstat-tp7394459p7401439.html Sent from the R-sig-geo mailing list archive at Nabble.com. _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo