[R-sig-Geo] krige.cv with nfold=1

[Francois JOUVIE]

Hello All,

I'm using for the first time the gstat command  krige.cv for cross  
validation.

Having some problems to perform with my own data, I tried with the  
data included with R which are often used in presentations (meuse data  
more precisely).
Then I tried the following commands which all perform:

 > data(meuse)
 > m<-vgm(.5,"Sph",900,0.04)
 > x<-krige.cv(log(zinc)~1,~x+y,meuse,m,nfold=5)
[using ordinary kriging]
[using ordinary kriging]
[using ordinary kriging]
[using ordinary kriging]
[using ordinary kriging]
 >

But if I want  nfold=1 (= not sub_divisions of the data ?) I get this  
(in French) :

 > x<-krige.cv(log(zinc)~1,~x+y,meuse,m,nfold=1)
Erreur dans gstat.formula(d$formula, d$data) :
   no response variable present in formula
De plus : Warning messages:
1: In min(x) : aucun argument trouvé pour min ; Inf est renvoyé
2: In max(x) : aucun argument pour max ; -Inf est renvoyé
3: In min(x) : aucun argument trouvé pour min ; Inf est renvoyé
4: In max(x) : aucun argument pour max ; -Inf est renvoyé
 >

What is happens ?

Thanks you very much if you can help me.

Francois