[gdal-dev] convert lines to polygons

[Frank Warmerdam]

Bryan Keith wrote:
> Hello,
> 
> I'm using BuildPolygonFromEdges in ogr in an attempt to take some lines
> and convert them to polygons.  For a number of my sets of lines
> BuildPolygonFromEdges fails.  I think this is because the lines aren't
> closed.  Is there a way to put a tolerance into BuildPolygonFromEdges so
> that nodes within the tolerance are considered coincident?
> 
> Or is there another tool that will do what I want?  I used to use ArcInfo
> CLEAN to do this, but I don't have access to that tool.  I'm open to any
> suggestions, not just gdal/ogr tools.  Thank you.

Bryan,

GRASS has support for building a polygon topology from various input.
I think v.clean is the key command though I am not too familiar with it.

BuildPolygonsFromEdges() is primarily intended for already clean input
data - primarily for polygon assemble from topological formats.

Best regards,
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