hello, I work on map anamporphosis, and I have managed to : - import and view mif/mid in R - work on coordinates in R. But I don't get how I can transform a list of x, y, id in a sp object (or other) to visualize my transformation without having to go back in mapinfo (Actually I can see points, but I would like to see polygons) My data is organised as follow : x,y,id1,id2 x y are coordinates obviously id1 is the id of the polygon id2 is the id of the multipolygon (when an area is made of several polygon) I have tried to do it manually with a loop to make Polygon, then Polygons, then ... but it's dramatically slow -- View this message in context: http://r.789695.n4.nabble.com/maps-in-R-from-a-list-of-x-y-tp4646312.html Sent from the R help mailing list archive at Nabble.com.