[GRASS-user] Query: number of 'areas' reported in v.build output does not necessarily represent different geographical areas

[RichardC]

Is there any automated way of removing the overlaps, as they appear quite
extensive?

I imported a portion of the large shapefile (I get memory errors when
attempting the entire file) covering SEAsia (I'm interested in wetlands of
this region where I'm based) and overlapping appears quite extensive for
some areas - see attached images.

I get the following errors on importing using snapping of 1e-16:
*379547 input polygons*
Total area: 1.64146E+10 (423219 areas)
Overlapping area: 1.61761E+09 (11784 areas)
Area without category: 6.61882E+08 (55476 areas)

Number of boundaries: 653327
Number of centroids: 367743
Number of areas: 423219
Number of isles: 165688
Number of incorrect boundaries: 19
Number of areas without centroid: 55476

Richard
<http://osgeo-org.1560.x6.nabble.com/file/n5052461/overlap_seasia.jpg> 
<http://osgeo-org.1560.x6.nabble.com/file/n5052461/seaasia_layer1.jpg> 
<http://osgeo-org.1560.x6.nabble.com/file/n5052461/overlap_areas.jpg> 

Note about showing layer2 - when I change the colour of the feature (via
properties) it then displays all polygons and I have to re-run d.vect to
re-display just the overlapped areas: d.vect map=filename type=area layer=2



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