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<h2>DESCRIPTION</h2>
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-<em>v.distance</em> finds the nearest element in vector map (<em>to</em>)
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-for elements in vector map (<em>from</em>). Various information about
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+<em>v.distance</em> finds the nearest element in vector map (<b>to</b>)
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+for elements in vector map (<b>from</b>). Various information about
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the vectors' relationships (distance, category, etc.) may be uploaded to
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the attribute table attached to the first vector map, or printed to
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'stdout'. A new vector map may be created where lines connecting
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-nearest points on features are written. <em>dmin</em> and/or
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-<em>dmax</em> can be used to limit the search radius.
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+nearest points on features are written. <b>dmin</b> and/or
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+<b>dmax</b> can be used to limit the search radius.
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<p>
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For lines to lines, say line A to line B, <em>v.distance</em> calculates
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@@ -36,21 +36,22 @@ area is used as common point, or the first intersection point.
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For anything else than points to lines, there can be several common
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locations with zero distance, and the common location would then be the
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result of an overlay consisting of several points, lines, or areas.
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-<em>v.distance</em> selects in these cases a single point, and does not
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-create an overlay like <em>v.overlay</em>. In this implementation, any
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-shared point is as good as any other. Calculating an intersection is
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-costlier than to check if a vertex is inside a polygon. For example, if
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-a vertex of the boundary of the 'to' area is inside the 'from' area, it
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-is a common location. For speed reasons, the distance is then set to
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-zero and no further tests are done.
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+<em>v.distance</em> selects in these cases a single point, and does
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+not create an overlay
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+like <em><a href="v.overlay.html">v.overlay</a></em>. In this
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+implementation, any shared point is as good as any other. Calculating
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+an intersection is costlier than to check if a vertex is inside a
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+polygon. For example, if a vertex of the boundary of the 'to' area is
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+inside the 'from' area, it is a common location. For speed reasons,
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+the distance is then set to zero and no further tests are done.
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<h2>NOTES</h2>
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If a nearest feature does not have a category, the attribute column is
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-updated to <em>null</em>.
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-<p>The upload <em>column</em>(s) must already exist. Create one with
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-<em>v.db.addcolumn</em>.
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+updated to NULL.
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+<p>The upload <b>column</b>(s) must already exist. Create one with
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+<em><a href="v.db.addcolumn.html">v.db.addcolumn</a></em>.
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<!-- needs Vect_line_geodesic_distance()
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<p>In lat-long locations <em>v.distance</em> gives distances
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@@ -62,10 +63,10 @@ calculated as geodesic distances on a sphere.
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<h3>Find nearest lines</h3>
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-Find <em>nearest lines</em> in vector map <b>ln</b> for points from
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-vector map <b>pnt</b> within the given threshold and write related
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-line categories to column <b>linecat</b> in an attribute table attached
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-to vector map <b>pnt</b>:
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+Find <em>nearest lines</em> in vector map "ln" for points from
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+vector map "pnt" within the given threshold and write related
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+line categories to column "linecat" in an attribute table attached
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+to vector map "pnt":
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<div class="code"><pre>
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v.distance from=pnt to=ln upload=cat column=linecat
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@@ -73,10 +74,10 @@ v.distance from=pnt to=ln upload=cat column=linecat
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<h3>Find nearest area</h3>
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-For each point from vector map <b>pnt</b>, find the <em>nearest area</em>
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-from map <b>ar</b> within the given threshold and write the related
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-area categories to column <b>areacat</b> in an attribute table attached
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-to vector map <b>pnt</b> (in the case that a point falls into an area,
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+For each point from vector map "pnt", find the <em>nearest area</em>
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+from map "ar" within the given threshold and write the related
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+area categories to column "areacat" in an attribute table attached
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+to vector map "pnt" (in the case that a point falls into an area,
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the distance is zero):
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<div class="code"><pre>
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@@ -86,7 +87,7 @@ v.distance from=pnt to=ar upload=cat column=areacat
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<h3>Create a new vector map</h3>
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Create a new vector map which contains <em>lines connecting nearest
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-features</em> of maps <b>pnt</b> and map <b>ln</b>. The resulting
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+features</em> of maps "pnt" and map "ln". The resulting
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vector map can be used for example to connect points to a network as
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needed for network analysis:
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@@ -114,14 +115,14 @@ v.distance from=pnt to=map_to_query upload=cat col=somecol -p
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<h3>Point-in-polygon</h3>
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-The option <em>dmax=0</em> is here important because otherwise for
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+The option <b>dmax=0</b> is here important because otherwise for
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points not falling into any area, the category of the nearest area is
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recorded.
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<br>
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-For each point from vector map <b>pnt</b>, find the <em>area</em> from
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-vector map <b>ar</b> in which the individual point falls, and
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-write the related area categories to column <b>areacat</b> into
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-the attribute table attached to vector map <b>pnt</b>:
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+For each point from vector map "pnt", find the <em>area</em> from
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+vector map "ar" in which the individual point falls, and
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+write the related area categories to column "areacat" into
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+the attribute table attached to vector map "pnt":
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<div class="code"><pre>
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v.distance from=pnt to=ar dmax=0 upload=cat column=areacat
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@@ -164,7 +165,7 @@ v.univar vdistance_vectors column=length
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v.distance -pa from=archsites to=archsites upload=dist col=dist
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</pre></div>
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-Note: Matrix-like output is enabled only for flag <em>-a</em> and one
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+Note: Matrix-like output is enabled only for flag <b>-a</b> and one
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given upload option.
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<h2>SEE ALSO</h2>
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@@ -183,6 +184,7 @@ Cmd line coordinates support: Markus Neteler, ITC-irst, Trento, Italy<br>
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Updated for 5.1: Radim Blazek, ITC-irst, Trento, Italy<br>
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Matrix-like output by Martin Landa, FBK-irst, Trento, Italy<br>
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Improved processing speed: Markus Metz<br>
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-Distance from any feature to any feature Markus Metz
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+Distance from any feature to any feature: Markus Metz
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-<p><i>Last changed: $Date$</i>
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+<p>
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+<i>Last changed: $Date$</i>
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