On Thu, Feb 12, 2015 at 11:16 PM, Markus Metz <[email protected]> wrote: > On Wed, Feb 11, 2015 at 9:34 PM, Markus Neteler <[email protected]> wrote: >> HI, >> >> I tried to import the NUTS3 map(s) from EU which leads to some obscur >> warnings (see below). While most can be solved with a "mild" snapping, >> still four islands are reported as an error. > > The islands are not reported as an error. The error is that 9912 areas > (2748 areas with snap=1e-8) overlap. It is up to the user to decide if > overlapping areas are ok or not. The G7.1 message reports that areas > are overlapping, this might be an error or not. The G7.0 message says > that overlapping areas are errors, which is wrong because overlapping > areas can indeed occur.
In this case, overlapping areas are ok because NUTS_RG_03M_2010.shp contains several different administrative levels which obviously overlap. If you want to import only one level, use v.in.ogr where="STAT_LEVL_ = X" with X in [0, 3]. Now there should be no more overlapping areas. Markus M > > With regard to the test data, I think I know this Europe NUTS3 > dataset. Some areas are double labeled, snapping will not help here. > You need to look at the overlapping areas (layer=2) and you need to > decide which label in layer=1 (the area has several labels in layer 1) > is most probably correct (hint: search for other areas with the same > label in layer 1). > > Markus M > >> They are Andorra, etc and >> apparently really valid. The error message though suggests that the >> import was not successful. Could this be fixed? >> >> # Download NUTS3 2010, 3M and 10M >> # >> http://ec.europa.eu/eurostat/web/gisco/geodata/reference-data/administrative-units-statistical-units >> >> # create new location from SHP file >> grass70 -c NUTS_BN_03M_2010.shp ~/grassdata/eu_etrs89 >> g.proj -w >> >> # import NUTS3 polygons (performs topology check) >> v.in.ogr input=NUTS_RG_03M_2010.shp output=NUTS_RG_03M_00 >> ... >> Cleaning polygons >> ----------------------------------------------------- >> Breaking polygons... >> ... >> ----------------------------------------------------- >> Building areas... >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> ... >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> 100% >> 16926 areas built >> 1325 isles built >> Number of nodes: 113763 >> Number of primitives: 355557 >> Number of points: 0 >> Number of lines: 0 >> Number of boundaries: 355557 >> Number of centroids: 0 >> Number of areas: 16926 >> Number of isles: 1325 >> WARNING: Number of incorrect boundaries: 157 >> ----------------------------------------------------- >> Removing bridges... >> 100% >> ----------------------------------------------------- >> Registering primitives... >> 48083 primitives registered >> 343316 vertices registered >> Building areas... >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> ... >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> 100% >> 16925 areas built >> 1335 isles built >> Attaching islands... >> 100% >> Number of nodes: 32451 >> Number of primitives: 48083 >> Number of points: 0 >> Number of lines: 0 >> Number of boundaries: 48083 >> Number of centroids: 0 >> Number of areas: 16925 >> Number of isles: 1335 >> WARNING: Number of incorrect boundaries: 36 >> WARNING: Vect_get_point_in_poly_isl(): collapsed area >> WARNING: Unable to calculate area centroid >> WARNING: Vect_get_point_in_poly_isl(): collapsed area >> WARNING: Unable to calculate area centroid >> WARNING: Vect_get_point_in_poly_isl(): collapsed area >> WARNING: Unable to calculate area centroid >> WARNING: Vect_get_point_in_poly_isl(): collapsed area >> ... >> WARNING: Unable to calculate area centroid >> WARNING: Vect_get_point_in_poly_isl(): collapsed area >> WARNING: Unable to calculate area centroid >> ----------------------------------------------------- >> Finding centroids for OGR layer <NUTS_RG_03M_2010>... >> 100% >> ----------------------------------------------------- >> Writing centroids... >> 100% >> WARNING: 9912 areas represent more (overlapping) features, because polygons >> overlap in input layer(s). Such areas are linked to more than 1 >> row in attribute table. The number of features for those areas is >> stored as category in layer 2 >> ----------------------------------------------------- >> 7007 input polygons >> Total area: 5.75852E+12 (16925 areas) >> Overlapping area: 5.74784E+12 (9912 areas) >> Area without category: 5.32057E+08 (19 areas) >> ----------------------------------------------------- >> Copying features... >> 100% >> Building topology for vector map <NUTS_RG_03M_2010@PERMANENT>... >> Registering primitives... >> 59076 primitives registered >> 354309 vertices registered >> Building areas... >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> ... >> WARNING: Area of size = 0.0 ignored >> WARNING: Area of size = 0.0 ignored >> 100% >> 16925 areas built >> 1335 isles built >> Attaching islands... >> 100% >> Attaching centroids... >> 100% >> Number of nodes: 32451 >> Number of primitives: 59076 >> Number of points: 0 >> Number of lines: 0 >> Number of boundaries: 48083 >> Number of centroids: 10993 >> Number of areas: 16925 >> Number of isles: 1335 >> WARNING: Number of incorrect boundaries: 36 >> ----------------------------------------------------- >> WARNING: Errors were encountered during the import >> Estimated range of snapping threshold: [1e-13, 1e-05] >> Try to import again, snapping with at least 1e-13: 'snap=1e-13' >> >> # --> the "WARNING: Vect_get_point_in_poly_isl(): collapsed area" >> looks like a debug message to an average user. >> >> >> >> # NEW ATTEMPT WITH SNAPPING >> GRASS 7.0.0svn (eu_etrs89): > v.in.ogr input=NUTS_RG_03M_2010.shp >> output=NUTS_RG_03M_2010 snap=1e-8 --o >> ... >> Writing centroids... >> 100% >> WARNING: 2748 areas represent more (overlapping) features, because polygons >> overlap in input layer(s). Such areas are linked to more than 1 >> row in attribute table. The number of features for those areas is >> stored as category in layer 2 >> ----------------------------------------------------- >> 7007 input polygons >> Total area: 5.75852E+12 (2759 areas) >> Overlapping area: 5.74784E+12 (2748 areas) >> Area without category: 5.32057E+08 (4 areas) >> ----------------------------------------------------- >> Copying features... >> 100% >> Building topology for vector map <NUTS_RG_03M_2010@PERMANENT>... >> Registering primitives... >> 8419 primitives registered >> 217332 vertices registered >> Building areas... >> 100% >> 2759 areas built >> 1315 isles built >> Attaching islands... >> 100% >> Attaching centroids... >> 100% >> Number of nodes: 4220 >> Number of primitives: 8419 >> Number of points: 0 >> Number of lines: 0 >> Number of boundaries: 5664 >> Number of centroids: 2755 >> Number of areas: 2759 >> Number of isles: 1315 >> ----------------------------------------------------- >> WARNING: Errors were encountered during the import >> Estimated range of snapping threshold: [1e-13, 1e-05] >> Try to import again, snapping with 1e-07: 'snap=1e-07' >> >> v.build NUTS_RG_03M_2010 error=NUTS_RG_03M_2010_errors >> ... >> Number of nodes: 4 >> Number of primitives: 4 >> Number of points: 0 >> Number of lines: 0 >> Number of boundaries: 4 >> Number of centroids: 0 >> Number of areas: 4 >> Number of isles: 4 >> >> The "WARNING: Errors were encountered during the import" is scary >> while it seems to be valid islands (Andorra, San Marino, two islands >> near Rome). >> >> thanks >> Markus >> _______________________________________________ >> grass-dev mailing list >> [email protected] >> http://lists.osgeo.org/mailman/listinfo/grass-dev _______________________________________________ grass-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-dev
