Difference between revisions of "Vector topology cleaning"

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(screenshot example added)
(+notes from Markus Metz)
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Tools to consider:
 
Tools to consider:
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* TBD
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* ...
  
... TBD
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----
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'''Q:''' How about self-intersecting lines and boundaries?
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'''A:''' In the GRASS topological model self-intersecting lines are allowed, self-intersecting boundaries are not.
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Self-intersecting lines are ok e.g. for {{cmd|v.net}} modules, e.g. to represent a bridge of a secondary road over a highway.
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Note: There are some modules that do not like self-intersecting lines, e.g with {{cmd|v.buffer}} problems are expected.

Revision as of 13:56, 23 November 2011

Q: How can I patch to fitting area maps with have been digitized separately and correct the topology? I observe that the shared polygon boundaries do not perfectly match...

Polygon vector map with topology problems

A: You can use v.clean for this.

Tools to consider:

  • TBD
  • ...

Q: How about self-intersecting lines and boundaries?

A: In the GRASS topological model self-intersecting lines are allowed, self-intersecting boundaries are not. Self-intersecting lines are ok e.g. for v.net modules, e.g. to represent a bridge of a secondary road over a highway.

Note: There are some modules that do not like self-intersecting lines, e.g with v.buffer problems are expected.