[STATSGRASS] ORDINARY KRIGING IN R WITH GRASS6 DATA

[epifanio epi]

i'm trying to use the ORDINARY KRIGING IN R WITH GRASS6 DATA



i've in a grass location a vector file ( type : point) its name is :  
vector_point

i open R and type :

 > library(spgrass6)
Carico il pacchetto richiesto: rgdal
Carico il pacchetto richiesto: sp
Carico il pacchetto richiesto: abind
Carico il pacchetto richiesto: pixmap
Geospatial Data Abstraction Library extensions to R successfully loaded
Carico il pacchetto richiesto: sp
Warning message:
cannot create HTML package index in: make.packages.html()

then as the example at the web page :
http://grass.gdf-hannover.de/twiki/pub/GRASS/WebHome/ 
krigingusingRGRASS6.txt

i type :

 > giaciture <- getSites6sp("vector_point")
Errore: non trovo la funzione "getSites6sp"

why R do not find :  getSites6sp - function ?
canyou helpe me ?
thank's!
Massimo