fortify.SpatialPolygonsDataFrame error

Hi everyone, 

I would like to know if someone of you has already got troubles when trying to use ggplot2 with a shape file?
Here is what I've done:

NUTS1<-readShapeSpatial("nuts1_2003", proj4string=CRS(projargs=("+init=epsg:3035")),IDvar="NUTS1")
plot(NUTS1)

NUTS1 at data$id <- rownames(NUTS1 at data) 

# as codes are characters and not numeric values, I've changed them into:

test<-as.numeric(seq(1:94))
NUTS1 at data$id<-test

NUTS1.points <- fortify.SpatialPolygonsDataFrame(NUTS1, region="id")

# The function doesn't want to be applied and I get this error message:

Erreur dans unionSpatialPolygons(cp, invert(polys)) : input lengths differ
De plus : Message d'avis :
In split(as.numeric(row.names(attr)), addNA(attr[, region], TRUE)) :
  NAs introduits lors de la conversion automatique

(sorry for the French comments...)


# What I would like to do at the end is :

NUTS1.map <- ggplot()+geom_polygon(data=NUTS1.points, aes(long, lat, group=group), fill=NA, colour="black") + coord_map()


Do you have any idea of what I'm doing wrong?

Thanks you very much for your help!!!
Marion

 		 	   		  
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