Oliver, The problem with your rings isn't that they are not closed, it is that they are degenerate.
For instance: (559560.19 142169.94,559550.64 142173.43,559560.19 142169.94) This goes from PointA to PointB back to PointA. It is closed, it just is degenerate. It has no area. I'm not aware of a super easy way of cleaning out such junk rings - you might need to explicitly test them and remove them if they are degenerate. Best regards, On Wed, Aug 22, 2012 at 9:13 AM, Oliver Christen <oliver.chris...@camptocamp.com> wrote: > dear community > > first of all please accept my apologies if this is not the correct > place to ask about such question. > > I am trying to manipulate some geometric data using the gdal/ogr > python lib and Im facing a problem when trying to transform invalid > ring into valid ring. > > I have polygons with unclosed holes and I expected the CloseRings > function to solve this for me, but unfortunately, that functions > doesnt seem to do anything (in my case). > > see below for a simply python testcase, > > if you could tell me if I am possibly not using that function > correctly or if there is a more correct way to do that, you would be > very welcome > > using python version 2.6.6 > osgeo ogr lib version 1.3.40 > > thank you very much for your attention > best regards > Oliver > > from osgeo import ogr > > wkt = "POLYGON ((559577.81 142165.04,559577.67 142161.79,559577.66 > 142161.16,559577.18 142139.0,559564.07 142140.84,559562.99 > 142132.4,559556.42 142134.85,559556.47 142134.96,559541.39 > 142140.58,559549.54 142162.4,559547.0200406529475 > 142163.310114102292573,559550.570425555342808 > 142173.455536680703517,559577.81 142165.04),(559559.95600777247455 > 142169.280249390256358,559550.996165407239459 > 142172.552877245907439,559550.996165407355875 > 142172.552877245907439,559547.909677243907936 > 142163.733065433305455,559550.443360350676812 > 142162.817994827404618,559542.290859716595151 > 142140.991299878398422,559557.417905980604701 > 142135.353766721702414,559557.367843619547784 > 142135.243629527511075,559562.407678314950317 > 142133.364239115995588,559563.465598454349674 > 142141.631689094298054,559576.497222575126216 > 142139.80268921770039,559576.960120304953307 > 142161.173134415294044,559576.970239149406552 > 142161.810621617711149,559577.084823867655359 > 142164.470624003995908,559577.084823867655359 > 142164.470624004025012,559570.876975534367375 > 142165.896950183814624,559564.754505693446845 > 142167.653979024267755,559564.75450569356326 > 142167.653979024296859,559559.956007772590965 > 142169.280249390256358,559559.95600777247455 > 142169.280249390256358),(559560.19 142169.94,559550.64 > 142173.43,559560.19 142169.94),(559564.97 142168.32,559560.19 > 142169.94,559564.97 142168.32),(559577.810000000172295 > 142165.04,559571.34395208011847 142166.499739240010967,559564.97 > 142168.32,559577.810000000172295 142165.04))" > > poly = ogr.CreateGeometryFromWkt(wkt) > > poly.IsValid() > ERROR 1: IllegalArgumentException: Invalid number of points in > LinearRing found 3 - must be 0 or >= 4 > False > > poly.CloseRings() > > poly.IsValid() > ERROR 1: IllegalArgumentException: Invalid number of points in > LinearRing found 3 - must be 0 or >= 4 > False > _______________________________________________ > gdal-dev mailing list > gdal-dev@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/gdal-dev -- ---------------------------------------+-------------------------------------- I set the clouds in motion - turn up | Frank Warmerdam, warmer...@pobox.com light and sound - activate the windows | http://pobox.com/~warmerdam and watch the world go round - Rush | Geospatial Software Developer _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/gdal-dev
