Performing a kriging
The iitial values at the ini argumento for likfit seems innapropriate for your data. some reasonable guesses for them would be var(Humidity) and 0.05*max(dist(cbind(X,Y))) Besides consider divide UTM values by 1000 expressing distance in km to avoid computations with large numbers Paulo Justiniano Ribeiro Jr LEG (Laboratorio de Estatistica e Geoinformacao) Universidade Federal do Parana Caixa Postal 19.081 CEP 81.531-990 Curitiba, PR - Brasil Tel: (+55) 41 3361 3573 VOIP: (+55) (41) (3361 3600) 1053 1066 Fax: (+55) 41 3361 3141 e-mail: paulojus AT ufpr br http://www.leg.ufpr.br/~paulojus
On Thu, 13 Jun 2013, Komine wrote:
Dear,
I use the data (.csv) shown below for performing a kriging.
X Y Humidity
1 719134.1 1433671 90
2 736867.3 1431585 50
3 751471.1 1422197 32
4 749384.8 1414895 75
5 732694.8 1413851 12
6 719134.1 1412808 65
I use this code retreived from internet and adapted with my data.
tab<-read.table("C:\\Users\\Kriging.csv",sep=";",dec=",",header=TRUE)
tab
library(geoR)
ml <- likfit(Kriging, ini = c(1,0.5), fix.nugget =T)
pred.grid <- expand.grid(seq(0,1, l=51), seq(0,1, l=51))
kc <- krige.conv(Kriging, loc = pred.grid, krige = krige.control(obj.m =
ml))
image(kc, loc = pred.grid, col=gray(seq(1,0.1,l=30))
When I run the code, I have an error message from the fourth command line. Thank you in advance for your advice, I am not familiar with in spatial statistics. Komine -- View this message in context: http://r-sig-geo.2731867.n2.nabble.com/Performing-a-kriging-tp7583773.html Sent from the R-sig-geo mailing list archive at Nabble.com.
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