Hi, I'm a GIS novice, trying to reproject a vector layer. My objective is to get a world map projected into Lambert Equal-Area, centered on the north pole. I chose this projection as it shows the entire arctic well, but I don't have to use Lambert Equal-Area specifically.
This is what I've tried so far: Created a new location with the location wizard, selecting 'read projection and datum terms from georeferenced data file' The target file was: WorldCountries.shp retrieved from http://www.sharegeo.ac.uk/handle/10672/124 This appears to be correct, as I now have my location world-ll, which contains in the PERMANENT mapset the layer WorldCountries. The region info is: g.region -p projection: 3 (Latitude-Longitude) zone: 0 datum: wgs84 ellipsoid: wgs84 north: 83:37:38.7084N south: 90S west: 180W east: 180E nsres: 8:40:52.93542 ewres: 18 rows: 20 cols: 20 cells: 400 I then made a new location, using the wizard again: select coordinate system from a list: laea central parallel: 90 central meridian: 100 false northing: 0 false easting: 0 datum code: wgs84 I then set the extent to 90N, -90S, 180E, -180W, NS resolution 0.1, EW resolution 0.1 The resulting region info is: g.proj -p -PROJ_INFO------------------------------------------------- name : Lambert Azimuthal Equal Area proj : laea datum : wgs84 ellps : wgs84 lat_0 : 90 lon_0 : 100 x_0 : 0 y_0 : 0 no_defs : defined -PROJ_UNITS------------------------------------------------ unit : meter units : meters meters : 1 >From here I used the gui to import the WorldCountries vector layer from world-ll, generating the command: v.proj input=WorldCountries location=world-ll mapset=PERMANENT output=WorldCountries This command runs without error, but with a few suspicious warnings: v.proj input=WorldCountries location=world-ll mapset=PERMANENT output=WorldCountries Building topology for vector map <WorldCountries>... Registering primitives... 55402 primitives registered 417249 vertices registered Building areas... Area of size = 0.0 ignored Area of size = 0.0 ignored 27423 areas built 26809 isles built Attaching islands... Attaching centroids... Number of nodes: 54788 Number of primitives: 55402 Number of points: 0 Number of lines: 0 Number of boundaries: 28000 Number of centroids: 27402 Number of areas: 27423 Number of isles: 26809 Number of incorrect boundaries: 1 Number of centroids outside area: 1 Number of areas without centroid: 22 At this point, the WorldCountries layer appears in the Map Layers tab, but not on the display. Zooming to selected layer produces an error: Unable to zoom to vector map <WorldCountries@PERMANENT> What have I done wrong? Thanks! Tyler
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