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<em>v.select</em> allows the user to select features from a vector
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map by features from another one.
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<p>Supported operators (without GEOS):
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<li><b>overlap</b> - features partially or completely overlap
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Supported operators (with GEOS):
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<li><b>equals</b> - features are spatially equals</li>
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<li><b>disjoint</b> - features do not spatially intersect</li>
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<li><b>intersects</b> - features spatially intersect</li>
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<li><b>touches</b> - features spatially touches</li>
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<li><b>crosses</b> - features spatially crosses</li>
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<li><b>within</b> - feature A is completely inside feature B</li>
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<li><b>contains</b> - feature B is completely inside feature A</li>
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<li><b>overlaps</b> - features spatially overlap</li>
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<li><b>relate</b> - feature A is spatially related to feature B</li>
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Only features with category numbers will be considered. If required
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the <em><a href="v.category.html">v.category</a></em> module can be
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used to add them. Typically boundaries do not need to be given a
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category number, as an area's attributes are inherited from the
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centroid. Typically points, lines, and centroids will always want to
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have a cat number. E.g. take a road which separates two farms. It is
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ambiguous as to which farm an attribute that is attached to the road
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belongs to. The boundary only needs a cat number if it will hold its
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own attributes, such as road name or pavement form. A centroid in each
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paddock holds the information with respect to ownership, area, etc.
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Extract fire stations (points) from urban area map (polygon) - North Carolina
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<div class="code"><pre>
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v.select ainput=firestations binput=urbanarea output=urban_firestations \
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Extract Italian rivers from VMAP0 watercourses map:
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<div class="code"><pre>
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v.select ainput=watrcrsl_eurnasia_wgs84 binput=italy_area \
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output=watrcrsl_italy operator=overlap
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Processing areas with GEOS is currently incredibly slow. Significant
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<a href="v.category.html">v.category</a>,
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<a href="v.overlay.html">v.overlay</a>,
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<a href="v.extract.html">v.extract</a>
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<a href="sql.html">GRASS SQL interface</a>
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GEOS support by Martin Landa, Czech Technical University in Prague, Czech Republic
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<i>Last changed: $Date: 2012-12-10 11:32:07 +0100 (Mon, 10 Dec 2012) $</i>