weird lines on map of country of Georgia

[hzt7]

I'm just running some very basic code and wondering what the weird lines are and how to get rid of them. (NOTE this is the country of Georgia, not the state of Georgia).

proc gmap
data=mapsgfk.georgia
map=mapsgfk.georgia;
id id1;
choro id1 ;
run;
quit;

[Rick_SAS]

I think the problem is that this data set has both ID and ID1 variables. Try this:

proc gmap data=mapsgfk.georgia
map=mapsgfk.georgia;
id ID;
choro id1;
run;
quit;

[ballardw]

The general behavior results from polygons at one level not being quite closed in regards to the id variable.

Here's a brief example:

data example;
   input id x y id2;
datalines;
1 10 10 1 
1 10 15 1 
1 15 15 1 
1 15 10 1 
1 16 27 2 
1 25 27 2 
1 25 12 2 
1 16 12 2 
;
run;

proc gmap map=example data=example;
   id id;
   choro id;
run;
quit;


proc gmap map=example data=example;
   id id2;
   choro id2;
run;
quit;

Note that for ID the boundary continues (connects to) the area identified with id2 when using ID.