[R-sig-Geo] ring not closed - readShapePoly - read.shape - maptools

[Patrick Giraudoux]

OK... after a check, none of the rings are closed... suppose closing was 
managed automatically by ArcGIS and read.Shape...


Patrick Giraudoux a écrit :
> Hi,
>
> I have slept on some data of a project which started in 2003 and  just 
> coming back on them today gives the opportunity to compare read.shape 
> (shapefiles were initially imported with this function) and 
> readShapePoly (the new one sp style). The latter will be much more 
> interesting for the next step, giving directed handling to overlay 
> methods.
>
> Importing one of my shapefile with read.shape ( read as polyshape in 
> ArcGIS) made (and still makes) no problem. However, when I try to 
> import it again via readShapePoly, I get this message:
>
> > UG<-readShapePoly("U:/Documents and Settings/giraudoux/Mes 
> documents/FC25/NewSIG050317/UG.shp")
> Error in validityMethod(object) : ring not closed
>
> Clear enough: at least one of the polygons is not closed... which is 
> confirmed by the fact that I can import the shapefile easy with 
> readShapeLines. I suppose the readShapePoly is more demanding in 
> validity control than the older read.Shape and ArcGIS: one cannot 
> complain for that.
>
> I am not afraid of sorting this out with some lines of programme. I 
> have however a question before writing it: is there already a function 
> making a check somewhere which could be used to know which one(s) of 
> the polygons are not closed?
>
> Patrick
>
>
>
>