[GRASS-SVN] r56389 - in grass/trunk/vector: v.net v.net.alloc v.net.bridge v.net.centrality v.net.components v.net.connectivity v.net.distance v.net.flow v.net.iso v.net.path v.net.salesman v.net.spanningtree v.net.timetable v.net.visibility
svn_grass at osgeo.org
svn_grass at osgeo.org
Thu May 23 12:59:24 PDT 2013
Author: neteler
Date: 2013-05-23 12:59:24 -0700 (Thu, 23 May 2013)
New Revision: 56389
Modified:
grass/trunk/vector/v.net.alloc/v.net.alloc.html
grass/trunk/vector/v.net.bridge/v.net.bridge.html
grass/trunk/vector/v.net.centrality/v.net.centrality.html
grass/trunk/vector/v.net.components/v.net.components.html
grass/trunk/vector/v.net.connectivity/v.net.connectivity.html
grass/trunk/vector/v.net.distance/v.net.distance.html
grass/trunk/vector/v.net.flow/v.net.flow.html
grass/trunk/vector/v.net.iso/v.net.iso.html
grass/trunk/vector/v.net.path/v.net.path.html
grass/trunk/vector/v.net.salesman/v.net.salesman.html
grass/trunk/vector/v.net.spanningtree/v.net.spanningtree.html
grass/trunk/vector/v.net.timetable/v.net.timetable.html
grass/trunk/vector/v.net.visibility/v.net.visibility.html
grass/trunk/vector/v.net/v.net.html
Log:
v.net.*: HTML layout fixes
Modified: grass/trunk/vector/v.net/v.net.html
===================================================================
--- grass/trunk/vector/v.net/v.net.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net/v.net.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -1,16 +1,17 @@
<h2>DESCRIPTION</h2>
-<em>v.net</em> is used for network preparation and maintenance. Its main
-use is to create a vector network from vector lines (<em>arcs</em>) and points
-(<em>nodes</em>) by creating nodes from intersections in a map of vector
-lines (<em>node</em> operator), by connecting a vector lines map with a points map
-(<em>connect</em> operator), and by creating new lines between pairs of vector points
+<em>v.net</em> is used for network preparation and maintenance. Its
+main use is to create a vector network from vector lines (<em>arcs
+</em>) and points (<em>nodes</em>) by creating nodes from
+intersections in a map of vector lines (<em>node</em> operator), by
+connecting a vector lines map with a points map (<em>connect</em>
+operator), and by creating new lines between pairs of vector points
(<em>arcs</em> operator).
<p>
A GIS network consists of topologically correct lines (arcs). That is,
the lines must be connected by shared vertices where real connections exist.
-In GRASS you also can add nodes to the network. These are specially
+In GRASS GIS you also can add nodes to the network. These are specially
designated vertices used for analyzing network properties or computing
cost/distance measures. That is, not all vertices are treated as nodes by
default. Only <em><a href="v.net.path.html">v.net.path</a></em> can use a
@@ -23,29 +24,32 @@
method to add arcs to a set of nodes:
<ol>
-<li>Use the <em>connect</em> operation to create nodes from a vector points
-file and add these nodes to an existing vector network of arcs (i.e.,
-lines/boundaries). This is useful when the goal is to analyze a set of places
-(points) in relation to a network--for example travel costs between places.
-Only points within the <em>thresh</em> (threshold) distance to a line/boundary
-will be connected as network nodes. There are two ways to connect nodes. By
-default, <em>v.net</em> will create new lines connecting each point to
-the closest line of the network. If you use the <em>-s</em> flag,
-however, the new nodes will be added on the closest line of the network at the
-point closest to the point you wish to add.</li>
+<li>Use the <em>connect</em> operation to create nodes from a vector
+points file and add these nodes to an existing vector network of
+arcs (i.e., lines/boundaries). This is useful when the goal is to
+analyze a set of places (points) in relation to a network--for
+example travel costs between places. Only points within the
+<em>thresh</em> (threshold) distance to a line/boundary will be
+connected as network nodes. There are two ways to connect nodes. By
+default, <em>v.net</em> will create new lines connecting each point
+to the closest line of the network. If you use the <em>-s</em> flag,
+however, the new nodes will be added on the closest line of the
+network at the point closest to the point you wish to add.</li>
-<li>Create nodes and arcs from a vector line/boundary file using the <em>node</em>
-operation. This is useful if you are mostly interested in the
-network itself and thus you can use intersections of the network as start and
-end points. Nodes will be created at all intersections of two or more lines.
-For an <em>arc</em> that consists of several segments connected by
-vertices (the typical case), only the starting and ending vertices are
-treated as network nodes.</li>
+<li>Create nodes and arcs from a vector line/boundary file using the
+<em>node</em> operation. This is useful if you are mostly interested
+in the network itself and thus you can use intersections of the
+network as start and end points. Nodes will be created at all
+intersections of two or more lines. For an <em>arc</em> that
+consists of several segments connected by vertices (the typical
+case), only the starting and ending vertices are treated as network
+nodes.</li>
-<li>Create straight-line arcs between pairs of nodes with the <em>arcs</em> option.
-This produces networks like those of airline flights between airports. It is
-also similar to the kind of network created with social networking
-software, making it possible to create georeferenced social networks.</li>
+<li>Create straight-line arcs between pairs of nodes with the
+<em>arcs</em> option. This produces networks like those of airline
+flights between airports. It is also similar to the kind of network
+created with social networking software, making it possible to
+create georeferenced social networks.</li>
</ol>
<p>
@@ -55,24 +59,25 @@
information.
<p>
-For nodes created using the <em>connect</em> and <em>arcs</em> operations (methods 1
-and 3 above), the nodes can be reconnected to the attribute table of the
-input vector points file using the attribute table manager ("manage layers"
-tab) or by running <em><a href="v.db.connect.html">v.db.connect</a></em>.
+For nodes created using the <em>connect</em> and <em>arcs</em>
+operations (methods 1 and 3 above), the nodes can be reconnected to
+the attribute table of the input vector points file using the
+attribute table manager ("manage layers" tab) or by running
+<em><a href="v.db.connect.html">v.db.connect</a></em>.
<p>
-For nodes created using the <em>nodes</em> operation
-(method 2 above), it is possible to create an attribute table for the
-new nodes in layer 2 using the attribute table manager and connect it to
+For nodes created using the <em>nodes</em> operation (method 2
+above), it is possible to create an attribute table for the new
+nodes in layer 2 using the attribute table manager and connect it to
layer 2 ("manage layers" tab) or to create a table with
<em><a href="v.db.addtable.html">v.db.addtable</a></em>,
connect it to layer 2 with <em><a href="v.db.connect.html">v.db.connect</a></em>,
and update the new table with cat values with <em><a href="v.to.db.html">v.to.db</a></em>.
<p>
-Once a vector network has been created, it can be analyzed in a number
-of powerful ways using the suite of <em>v.net</em>.* modules. The shortest route
-between two nodes, following arcs, can be computed
+Once a vector network has been created, it can be analyzed in a
+number of powerful ways using the suite of <em>v.net</em>.* modules.
+The shortest route between two nodes, following arcs, can be computed
(<em><a href="v.net.path.html">v.net.path</a></em>), as can the
shortest route that will pass through a set of nodes and return to the
starting node (<em><a href="v.net.salesman.html">v.net.salesman</a></em>).
@@ -124,17 +129,20 @@
Merge in nodes from a separate map within given threshold:
<div class="code"><pre>
-v.net input=streets_wake points=firestations out=streets_net operation=connect thresh=500
+v.net input=streets_wake points=firestations out=streets_net \
+ operation=connect thresh=500
</pre></div>
-For generating network for given vector point map is required input file in format
+For generating network for given vector point map is required input
+file in format:
<div class="code"><pre>
[category of edge] [category of start node] [category of end node]
</pre></div>
<div class="code"><pre>
-v.net points=geodetic_swwake_pts output=geodetic_swwake_pts_net operation=arcs file=- << EOF
+v.net points=geodetic_swwake_pts output=geodetic_swwake_pts_net \
+ operation=arcs file=- << EOF
> 1 28000 28005
> 2 27945 27958
> 3 27886 27897
Modified: grass/trunk/vector/v.net.alloc/v.net.alloc.html
===================================================================
--- grass/trunk/vector/v.net.alloc/v.net.alloc.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.alloc/v.net.alloc.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -1,24 +1,29 @@
<h2>DESCRIPTION</h2>
-<em>v.net.alloc</em> allocates subnets for nearest centers (direction from
-center). center nodes must be opened (costs >= 0). Costs of center nodes are
-used in the calculation.
-<p>Costs may be either line lengths, or attributes saved in a database
-table. These attribute values are taken as costs of whole segments, not
-as costs to traverse a length unit (e.g. meter) of the segment.
-For example, if the speed limit is 100 km / h, the cost to traverse a
-10 km long road segment must be calculated as
+<em>v.net.alloc</em> allocates subnets for nearest centers
+(direction from center). center nodes must be opened (costs >= 0).
+Costs of center nodes are used in the calculation.
+<p>
+Costs may be either line lengths, or attributes saved in a
+database table. These attribute values are taken as costs of whole
+segments, not as costs to traverse a length unit (e.g. meter) of the
+segment. For example, if the speed limit is 100 km / h, the cost to
+traverse a 10 km long road segment must be calculated as
+<br>
length / speed = 10 km / (100 km/h) = 0.1 h.
+<br>
Supported are cost assignments for both arcs and nodes,
and also different costs for both directions of a vector line.
For areas, costs will be calculated along boundary lines.
-<p>The input vector needs to be prepared with <em>v.net operation=connect</em>
+<p>
+The input vector needs to be prepared with <em>v.net operation=connect</em>
in order to connect points representing center nodes to the network.
<h2>NOTES</h2>
Nodes and arcs can be closed using cost = -1.
-<p>Center nodes can also be assigned to vector nodes using
+<p>
+Center nodes can also be assigned to vector nodes using
<em><a href="wxGUI.Vector_Digitizer.html">wxGUI vector digitizer</a></em>.
<h2>EXAMPLES</h2>
Modified: grass/trunk/vector/v.net.bridge/v.net.bridge.html
===================================================================
--- grass/trunk/vector/v.net.bridge/v.net.bridge.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.bridge/v.net.bridge.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -1,39 +1,41 @@
<h2>DESCRIPTION</h2>
-<em>v.net.bridge</em> finds bridges and articulation points in a network.
+<em>v.net.bridge</em> finds bridges and articulation points in a network.
<h2>NOTES</h2>
-Bridge in a network is an edge/line whose removal would disconnect the
-(sub-)network. A node is an articulation point if its removal would
-disconnect the (sub-)network. For more information and formal definitions
-check the wikipedia entries:
+Bridge in a network is an edge/line whose removal would disconnect
+the (sub-)network. A node is an articulation point if its removal
+would disconnect the (sub-)network. For more information and formal
+definitions check the wikipedia entries:
<a href="http://en.wikipedia.org/wiki/Bridge_%28graph_theory%29">bridge</a>
-and <a href="http://en.wikipedia.org/wiki/Cut_vertex">articulation point</a>.<br><br>
-The output of the module contains the selected features. For
-<b>method=bridge</b>, lines corresponding to bridges are copied from
-the input map to the output map. On the other hand, for
-<b>method=articulation</b>, points are created on the positions of
-articulation points.<br><br>
+and <a href="http://en.wikipedia.org/wiki/Cut_vertex">articulation
+point</a>.
+<p>
+The output of the module contains the selected
+features. For <b>method=bridge</b>, lines corresponding to
+bridges are copied from the input map to the output map. On the
+other hand, for <b>method=articulation</b>, points are created on
+the positions of articulation points.
+<p>
+<br>In GRASS GIS, <em>line</em> is not always a single line
+segment. It might be, and often is, a sequence of line segments
+between two intersections. Also, articulation point is a standard
+graph theoretic terminology which is slightly misleading in GRASS.
+An articulation point in graph theory is an articulation
+<em>node</em> in GRASS terminology.
-<br>In GRASS, <em>line</em> is not always a single line segment. It
-might be, and often is, a sequence of line segments between two
-intersections. Also, articulation point is a standard graph theoretic
-terminology which is slightly misleading in GRASS. An articulation point
-in graph theory is an articulation <em>node</em> in GRASS terminology.
-
<h2>EXAMPLES</h2>
<div class="code"><pre>
+ TBD
</pre></div>
-<p>
-<div class="code"><pre>
-</pre></div>
<h2>SEE ALSO</h2>
<em>
+<a href="v.net.html">v.net</a>,
<a href="v.category.html">v.category</a>,
</em>
Modified: grass/trunk/vector/v.net.centrality/v.net.centrality.html
===================================================================
--- grass/trunk/vector/v.net.centrality/v.net.centrality.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.centrality/v.net.centrality.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -1,42 +1,43 @@
<h2>DESCRIPTION</h2>
-<em>v.net.centrality</em> computes degree, closeness, betweenness and
-eigenvector centrality measures.
+<em>v.net.centrality</em> computes degree, closeness, betweenness
+and eigenvector centrality measures.
<h2>NOTES</h2>
-The module computes various centrality measures for each node and stores
-them in the given columns of an attribute table, which is created and
-linked to the output map. For the description of these, please check the
-following <a href="http://en.wikipedia.org/wiki/Centrality">wikipedia article</a>.
+The module computes various centrality measures for each node and
+stores them in the given columns of an attribute table, which is
+created and linked to the output map. For the description of these,
+please check the following
+<a href="http://en.wikipedia.org/wiki/Centrality">wikipedia article</a>.
If the column name is not given for a measure then that measure is not
-computed. If <b>-a</b> flag is set then points are added on nodes without
-points. Also, the points for which the output is computed can be specified
-by <b>cats</b>, <b>layer</b> and <b>where</b> parameters. However, if any
-of these parameters is present then <b>-a</b> flag is ingored and no new
-points are added.<br>
+computed. If <b>-a</b> flag is set then points are added on nodes
+without points. Also, the points for which the output is computed
+can be specified by <b>cats</b>, <b>layer</b> and <b>where</b>
+parameters. However, if any of these parameters is present then
+<b>-a</b> flag is ignored and no new points are added.
+<br>
Betweenness measure is not normalised. In order to get the normalised
-values (between 0 and 1), each number needs to be divided by
-<em>N choose 2=N*(N-1)/2</em> where N is the number of nodes in the
-connected component. Computation of eigenvector measure terminates if
-the given number of iterations is reached or the cummulative <em>squared</em>
-error between the successive iterations is less than <b>error</b>.
+values (between 0 and 1), each number needs to be divided by <em>N
+choose 2=N*(N-1)/2</em> where N is the number of nodes in the
+connected component. Computation of eigenvector measure terminates
+if the given number of iterations is reached or the cummulative <em>
+squared</em> error between the successive iterations is less than <b>
+error</b>.
<h2>EXAMPLES</h2>
-Compute closeness and betweenness centrality measures for each node and
-produce a map containing not only points already present in the input map
-but a map with point on every node.
+Compute closeness and betweenness centrality measures for each node
+and produce a map containing not only points already present in the
+input map but a map with point on every node.
<div class="code"><pre>
-v.net.centrality input=roads output=roads_cent closeness=close betweenness=betw -a
+v.net.centrality input=roads output=roads_cent closeness=closeness \
+ betweenness=betweenness -a
</pre></div>
-<p>
-<div class="code"><pre>
-</pre></div>
-
<h2>SEE ALSO</h2>
<em>
+<a href="v.net.html">v.net</a>,
<a href="v.generalize.html">v.generalize</a>
</em>
Modified: grass/trunk/vector/v.net.components/v.net.components.html
===================================================================
--- grass/trunk/vector/v.net.components/v.net.components.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.components/v.net.components.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -4,20 +4,22 @@
components in a network.
<h2>NOTES</h2>
-Two nodes, <em>u</em> and <em>v</em> are in the same strongly connected
-component if there are directed paths from <em>u</em> to <em>v</em> and
-from <em>v</em> to <em>u</em>. The nodes are in the same weakly connected
-component if, ignoring orientation of the edges, there is a path between
-them.<br>
+Two nodes, <em>u</em> and <em>v</em> are in the same strongly
+connected component if there are directed paths from <em>u</em> to
+<em>v</em> and from <em>v</em> to <em>u</em>. The nodes are in the
+same weakly connected component if, ignoring orientation of the
+edges, there is a path between them.
+<br>
The type of components is specified by <b>method</b> parameter.
-<em>v.net.components</em> creates a table and links it to the given
-<b>layer</b>. This table contains only two integer columns: <em>cat</em>
-and <em>comp</em>. If a point or both endpoints of a line belong to the
-same component then the point/line is written to the output map and
-appropriate information is stored in the table. If <b>-a</b> flag is set
-then new points are added on the nodes without points. These points have
-category numbers larger than any category used in the input map.
+<em>v.net.components</em> creates a table and links it to the given <b>layer</b>.
+This table contains only two integer columns: <em>cat</em> and <em>comp
+</em>. If a point or both endpoints of a line belong to the same
+component then the point/line is written to the output map and
+appropriate information is stored in the table. If <b>-a</b> flag is
+set then new points are added on the nodes without points. These
+points have category numbers larger than any category used in the
+input map.
<h2>EXAMPLES</h2>
@@ -26,14 +28,11 @@
<div class="code"><pre>
v.net.components input=roads output=roads_components method=strong
</pre></div>
-<p>
-<div class="code"><pre>
-</pre></div>
-
<h2>SEE ALSO</h2>
<em>
+<a href="v.net.html">v.net</a>,
<a href="v.category.html">v.category</a>,
</em>
Modified: grass/trunk/vector/v.net.connectivity/v.net.connectivity.html
===================================================================
--- grass/trunk/vector/v.net.connectivity/v.net.connectivity.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.connectivity/v.net.connectivity.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -5,29 +5,33 @@
given sets.
<h2>NOTES</h2>
-Two sets (<em>set1</em> and <em>set2</em>) are specified by respective
-<b>layer</b>, <b>where</b> and <b>cats</b> parameters. Similarly to
-<a href="v.net.flow.html">v.net.flow</a> module, capacities of nodes can
-be given by <b>ncolumn</b> option. <em>v.net.connectivity</em> finds the
-set of nodes of minimum total capacitiy separating the two given sets and
-outputs map containing points on the positions of these nodes. Default
+Two sets (<em>set1</em> and <em>set2</em>) are specified by respective
+<b>layer</b>, <b>where</b> and <b>cats</b> parameters. Similarly to
+<a href="v.net.flow.html">v.net.flow</a> module, capacities of nodes can
+be given by <b>ncolumn</b> option. <em>v.net.connectivity</em> finds the
+set of nodes of minimum total capacitiy separating the two given sets and
+outputs map containing points on the positions of these nodes. Default
capacity, which is used when no column is specified, is one.
<h2>EXAMPLES</h2>
-The following command finds the minimum number of intersections separating
+The following command finds the minimum number of intersections separating
roads on the left bank from roads on the right bank.
<div class="code"><pre>
-v.net.connectivity input=roads output=roads_conn set1_where="bank=left" set2_where="bank=right"
+v.net.connectivity input=roads output=roads_conn set1_where="bank=left" \
+ set2_where="bank=right"
</pre></div>
<p>
+
<div class="code"><pre>
-v.net.connectivity input=airtraffic output=connectivity set1_where="name=JFK" set2_where="name=Heathrow" ncolumn=capacity
+v.net.connectivity input=airtraffic output=connectivity \
+ set1_where="name=JFK" set2_where="name=Heathrow" ncolumn=capacity
</pre></div>
<h2>SEE ALSO</h2>
<em>
+<a href="v.net.html">v.net</a>,
<a href="v.net.flow.html">v.net.flow</a>,
<a href="v.net.bridge.html">v.net.bridge</a>
</em>
Modified: grass/trunk/vector/v.net.distance/v.net.distance.html
===================================================================
--- grass/trunk/vector/v.net.distance/v.net.distance.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.distance/v.net.distance.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -1,38 +1,41 @@
<h2>DESCRIPTION</h2>
-<em>v.net.distance</em> finds the nearast element in set <em>to</em>
+<em>v.net.distance</em> finds the nearest element in set <em>to</em>
for every point in set <em>from</em>.
<h2>NOTES</h2>
-These two sets are given by the respective <b>layer</b>, <b>where</b>
-and <b>cats</b> parameters. The type of <em>to</em> features is specified
-by <b>to_type</b> parameter. All <em>from</em> features are <em>points</em>.
-A table is linked to <b>output</b> map containing various information
-about the relation. More specifically, the table has three columns:
-<em>cat</em>, <em>tcat</em> and <em>dist</em> storing category of each
-<em>from</em> feature, category of the nearest <em>to</em> feature and
-the distance between them respectively. Furthemore, <b>output</b> map
-contains the shorest path between each <em>cat</em>, <em>tcat</em> pair.
-Each path consist of several lines. If a line is on the shorest path
-from a point then the category of this point is assigned to the line.
-Note that every line may contain more than one category value since a
-single line may be on the shortest path for more than one <em>from</em>
-feature. And so the shortest paths can be easily obtained by querying
-lines with corresponding category number.
-<p>
+These two sets are given by the respective <b>layer</b>, <b>where</b>
+and <b>cats</b> parameters. The type of <em>to</em> features is
+specified by <b>to_type</b> parameter. All <em>from</em> features
+are <em>points</em>. A table is linked to <b>output</b> map
+containing various information about the relation. More
+specifically, the table has three columns: <em>cat</em>, <em>tcat</em>
+and <em>dist</em> storing category of each <em>from</em>
+feature, category of the nearest <em>to</em> feature and the
+distance between them respectively. Furthemore, <b>output</b> map
+contains the shorest path between each <em>cat</em>, <em>tcat</em>
+pair. Each path consist of several lines. If a line is on the
+shorest path from a point then the category of this point is
+assigned to the line. Note that every line may contain more than one
+category value since a single line may be on the shortest path for
+more than one <em>from</em> feature. And so the shortest paths can
+be easily obtained by querying lines with corresponding category
+number.
+<br>
The costs of arcs in forward and backward direction are specified by
-<b>afcolumn</b> and <b>abcolumn</b> columns respectively. If
+<b>afcolumn</b> and <b>abcolumn</b> columns respectively. If
<b>abcolumn</b> is not given, the same cost is used in both directions.
<p>
-<em>v.net.distance</em> will not work if you are trying to find the nearest
-neighbors within a group of nodes, i.e. where <em>to</em> and <em>from</em>
-are the same set of nodes, as the closest node will be the node itself and
-the result will be zero-length paths. In order to find nearest neighbors
-within a group of nodes, you can either loop through each node as <em>to</em>
-and all other nodes as <em>from</em> or create a complete distance matrix with
-<a href="v.net.allpairs.html">v.net.allpairs</a> and select the lowest non-zero
-distance for each node.
+<em>v.net.distance</em> will not work if you are trying to find the
+nearest neighbors within a group of nodes, i.e. where <em>to</em>
+and <em>from</em> are the same set of nodes, as the closest node
+will be the node itself and the result will be zero-length paths. In
+order to find nearest neighbors within a group of nodes, you can
+either loop through each node as <em>to</em> and all other nodes as
+<em>from</em> or create a complete distance matrix with
+<a href="v.net.allpairs.html">v.net.allpairs</a> and select the
+lowest non-zero distance for each node.
<h2>EXAMPLES</h2>
Find shortest path and distance from every school to the nearest hospital
Modified: grass/trunk/vector/v.net.flow/v.net.flow.html
===================================================================
--- grass/trunk/vector/v.net.flow/v.net.flow.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.flow/v.net.flow.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -1,46 +1,52 @@
<h2>DESCRIPTION</h2>
-<em>v.net.flow</em> computes the maximum flow and minimum cut between
-two sets of nodes.
+<em>v.net.flow</em> computes the maximum flow and minimum cut
+between two sets of nodes.
<h2>NOTES</h2>
-The two sets of nodes are called <em>sources</em> and <em>sink</em> and
-<em>v.net.flow</em> finds the maximimum flow from the former to the
-latter ones. Edge capacities can be specified by <b>afcolumn</b> for
-forward direction and <b>abcolumn</b> for backward direction. If the
-latter parameter is ommited then the same capacity is used in either
-direction. The sets are given by the respective <b>cats</b>, <b>layer</b>
-and <b>where</b> parameters. Maximum flow corresponds to the maximum
-amount of water possibly flowing through the network preserving the
-capacity constraints and minimum cut to the set of edges of minimum total
-capacity completely separating sources from sinks. The cut produced by
-this module corresponds to the first fully saturated edges from sources
-to sinks. An attribute table containing the flow information is linked
-to the <b>output</b> map. The table consists of two columns: <em>cat</em>
-and <em>flow</em> and stores the flow along each line. Negative flow
-means that "water" is flowing in the backward direction. <b>Cut</b> map
-contains the edges in the minimum cut. <br>
+The two sets of nodes are called <em>sources</em> and <em>sink</em>
+and <em>v.net.flow</em> finds the maximimum flow from the former to
+the latter ones. Edge capacities can be specified by <b>afcolumn</b>
+for forward direction and <b>abcolumn</b> for backward direction. If
+the latter parameter is ommited then the same capacity is used in
+either direction. The sets are given by the respective <b>cats</b>,
+<b>layer</b> and <b>where</b> parameters. Maximum flow corresponds
+to the maximum amount of water possibly flowing through the network
+preserving the capacity constraints and minimum cut to the set of edges
+of minimum total capacity completely separating sources from sinks.
+The cut produced by this module corresponds to the first fully
+saturated edges from sources to sinks. An attribute table containing
+the flow information is linked to the <b>output</b> map. The table
+consists of two columns: <em>cat</em> and <em>flow</em> and stores
+the flow along each line. Negative flow means that "water" is
+flowing in the backward direction. <b>Cut</b> map contains the edges
+in the minimum cut.
+<br>
A famous <a href="http://en.wikipedia.org/wiki/Max-flow_min-cut_theorem">result</a>
-says that the total amount of water flowing is equal to the minimum cut.
-
+says that the total amount of water flowing is equal to the minimum
+cut.
<h2>EXAMPLES</h2>
Find maximum flow from factories to stores using SPEED for the capacities.
<div class="code"><pre>
-v.net.flow input=roads output=roads_flow cut=roads_cut afcolumn=SPEED source_where="type=factory" sink_where="type=store"
+v.net.flow input=roads output=roads_flow cut=roads_cut afcolumn=SPEED \
+ source_where="type=factory" sink_where="type=store"
</pre></div>
<p>
+
If all the capacties are one then the minimum cut corresponds to the
minimum number of edges separating sources from sinks.
<div class="code"><pre>
-v.net.flow input=network output=flow cut=cut afcolumn=ones source_cats=1-10 sink_cats=100-100
+v.net.flow input=network output=flow cut=cut afcolumn=ones \
+ source_cats=1-10 sink_cats=100-100
</pre></div>
<h2>SEE ALSO</h2>
<em>
+<a href="v.net.html">v.net</a>,
<a href="v.net.connectivity.html">v.net.connectivity</a>
</em>
Modified: grass/trunk/vector/v.net.iso/v.net.iso.html
===================================================================
--- grass/trunk/vector/v.net.iso/v.net.iso.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.iso/v.net.iso.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -8,7 +8,9 @@
as costs to traverse a length unit (e.g. meter) of the segment.
For example, if the speed limit is 100 km / h, the cost to traverse a
10 km long road segment must be calculated as
+<br>
length / speed = 10 km / (100 km/h) = 0.1 h.
+<br>
Supported are cost assignments for both arcs and nodes,
and also different costs for both directions of a vector line.
For areas, costs will be calculated along boundary lines.
@@ -22,7 +24,6 @@
<p>
Nodes must be on the isolines.
-
<h2>EXAMPLES</h2>
The map must contain at least one center (point) on the vector network
Modified: grass/trunk/vector/v.net.path/v.net.path.html
===================================================================
--- grass/trunk/vector/v.net.path/v.net.path.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.path/v.net.path.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -9,7 +9,9 @@
as costs to traverse a length unit (e.g. meter) of the segment.
For example, if the speed limit is 100 km / h, the cost to traverse a
10 km long road segment must be calculated as
+<br>
length / speed = 10 km / (100 km/h) = 0.1 h.
+<br>
Supported are cost assignments for both arcs and nodes,
and also different costs for both directions of a vector line.
For areas, costs will be calculated along boundary lines.
Modified: grass/trunk/vector/v.net.salesman/v.net.salesman.html
===================================================================
--- grass/trunk/vector/v.net.salesman/v.net.salesman.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.salesman/v.net.salesman.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -7,8 +7,10 @@
table. These attribute values are taken as costs of whole segments, not
as costs to traverse a length unit (e.g. meter) of the segment.
For example, if the speed limit is 100 km / h, the cost to traverse a
-10 km long road segment must be calculated as
+10 km long road segment must be calculated as
+<br>
length / speed = 10 km / (100 km/h) = 0.1 h.
+<br>
Supported are cost assignments for arcs,
and also different costs for both directions of a vector line.
For areas, costs will be calculated along boundary lines.
Modified: grass/trunk/vector/v.net.spanningtree/v.net.spanningtree.html
===================================================================
--- grass/trunk/vector/v.net.spanningtree/v.net.spanningtree.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.spanningtree/v.net.spanningtree.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -1,17 +1,18 @@
<h2>DESCRIPTION</h2>
-<em>v.net.spanningtree</em> finds the minimum spanning tree in a network.
+<em>v.net.spanningtree</em> finds the minimum spanning tree in a
+network.
<h2>NOTES</h2>
A spanning tree is a minimum cost subnetwork connecting all nodes in a
-network. Or, if a network is disconnected then the module computes the
-minimum spanning tree for each (weakly) connected component. So, strictly
-speaking, <em>v.net.spanningtree</em> does not compute spanning tree but
-a spanning forest. As the name suggests, a spanning tree is a tree. That
-is, it contains no cycles and if a component has N nodes then the tree
-has N-1 edges connecting all nodes. <b>Accol</b> is used to specify the
-costs of the edges. The <b>output</b> consists of the edges in the
-spanning tree.
+network. Or, if a network is disconnected then the module computes
+the minimum spanning tree for each (weakly) connected component. So,
+strictly speaking, <em>v.net.spanningtree</em> does not compute spanning tree
+but a spanning forest. As the name suggests, a spanning tree is a tree. That
+is, it contains no cycles and if a component has N nodes then the
+tree has N-1 edges connecting all nodes. <b>Accol</b> is used to
+specify the costs of the edges. The <b>output</b> consists of the
+edges in the spanning tree.
<h2>EXAMPLES</h2>
@@ -19,10 +20,11 @@
<div class="code"><pre>
v.net.spanningtree input=projected_pipelines output=spanningtree accol=cost
</pre></div>
-<p>
+
<h2>SEE ALSO</h2>
<em>
+<a href="v.net.html">v.net</a>,
<a href="v.net.steiner.html">v.net.steiner</a>
</em>
Modified: grass/trunk/vector/v.net.timetable/v.net.timetable.html
===================================================================
--- grass/trunk/vector/v.net.timetable/v.net.timetable.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.timetable/v.net.timetable.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -1,26 +1,28 @@
<h2>DESCRIPTION</h2>
<em>v.net.timetable</em> finds the shortest path between two points
-using timetables. <em>v.net.timetable</em> reads input, one query per
-line, from the standard input and writes output to the standard output
-as well as to the <b>output</b> map and to tables linked to layers 1 and
-2. Each line of input must follow one of the following formats:
-<pre>
+using timetables. <em>v.net.timetable</em> reads input, one query per line,
+from the standard input and writes output to the standard output as well as
+to the <b>output</b> map and to tables linked to layers 1 and 2.
+Each line of input must follow one of the following formats:
+<div class="code"><pre>
PATH_ID FROM_X FROM_Y TO_X TO_Y START_TIME MIN_CHANGE MAX_CHANGES WALK_CHANGE
PATH_ID FROM_STOP TO_STOP START_TIME MIN_CHANGE MAX_CHANGES WALK_CHANGE
-</pre>
-where PATH_ID is the identificator of a query that is used in the output
-map to differentiate between queries. Search begins at START_TIME.
-MIN_CHANGE gives the minimum number of time (inclusively) for a change
-from one route to another. MAX_CHANGES denotes the maximum number of
-changes allowed or -1 if infinity. WALK_CHANGE is 1 or 0 depending whether
-walking from a stop to another stop is considered a change or not. Finally,
-the path is found from FROM_STOP to TO_STOP in latter case and from the
-stop closest to (FROM_X, FROM_Y) coordinates to the stop closest to
-(TO_X, TO_Y) coordinates in former case.<br>
-For each input query, module outputs a description of the shortest path
-to the standard output. For example, using the tables given below, for
-the following input:
+</pre></div>
+where PATH_ID is the identificator of a query that is used in the
+output map to differentiate between queries. Search begins at
+START_TIME. MIN_CHANGE gives the minimum number of time
+(inclusively) for a change from one route to another. MAX_CHANGES
+denotes the maximum number of changes allowed or -1 if infinity.
+WALK_CHANGE is 1 or 0 depending whether walking from a stop to
+another stop is considered a change or not. Finally, the path is
+found from FROM_STOP to TO_STOP in latter case and from the stop
+closest to (FROM_X, FROM_Y) coordinates to the stop closest to
+(TO_X, TO_Y) coordinates in former case.
+<br>
+For each input query, module outputs a description of the shortest
+path to the standard output. For example, using the tables given
+below, for the following input:
<div class="code"><pre>
47 130 300 0 1 5 0
</pre></div>
@@ -29,10 +31,10 @@
Route 15, from 130 leaving at 15 arriving to 250 at 22
Walk from 250 leaving at 22 arriving to 300 at 24
</pre></div>
-Moreover, the module writes the path to the <b>output</b> map and stores
-all the information necesasary to reconstruct the path to the tables.
-Table corresponding to stops/points is linked to layer 1 and looks,
-after the query, as follows:
+Moreover, the module writes the path to the <b>output</b> map and
+stores all the information necessary to reconstruct the path to the
+tables. Table corresponding to stops/points is linked to layer 1 and
+looks, after the query, as follows:
<div class="code"><pre>
cat|path_id|stop_id|index|arr_time|dep_time
1|47|130|1|0|15
@@ -40,48 +42,53 @@
3|47|300|3|24|24
</pre></div>
where CAT is the category of a point in the map, PATH_ID is the path
-identificator, STOP_ID is the identificator of the stop as used in the
-input map, INDEX is the index of the stop on the path (i.e, index=1 is
-the first stop visited, ...) and ARR_TIME and DEP_TIME denote the arrival
-time and departure time respectively. Arrival time for the first stop on
-the path is always equal to START_TIME and departure time for the last
-stop is always equal to the arrival time.<br>
-Table linked to the second layer corresponds to subroutes taken between
-stops. The following table is obtainedd for the above query:
+identificator, STOP_ID is the identificator of the stop as used in
+the input map, INDEX is the index of the stop on the path (i.e,
+index=1 is the first stop visited, ...) and ARR_TIME and DEP_TIME
+denote the arrival time and departure time respectively. Arrival
+time for the first stop on the path is always equal to START_TIME
+and departure time for the last stop is always equal to the arrival
+time.
+<br>
+The table linked to the second layer corresponds to subroutes taken
+between stops. The following table is obtainedd for the above query:
<div class="code"><pre>
cat|path_id|from_id|to_id|route_id|index|from_time|to_time
1|47|130|250|15|1|15|22
2|47|250|300|-1|2|22|24
</pre></div>
-where CAT is the category of lines of subroute between stops FROM_ID to
-TO_ID, ROUTE_ID is the identificator of the route taken or -1 if walking,
-INDEX and PATH_ID are as above and FROM_TIME and TO_TIME denote the times
-between which the route is taken.<br>
-The <b>output</b> map contains the points on the positions of used stops.
-If a subroute is taken between two stops then a line segment is added
-between two corresponding points. Finally, instead of straight line
-segment, the actual paths of routes can be given in <b>paths</b> layer.
-If this parameter is used then each line in the input map must contain
-identificators as category numbers of all routes passing through the line.
-The module then finds the path between two stops and writes this path
-instead. In case of walking from one stop to another, straight line
-between the stops is used.
+where CAT is the category of lines of subroute between stops FROM_ID
+to TO_ID, ROUTE_ID is the identificator of the route taken or -1 if
+walking, INDEX and PATH_ID are as above and FROM_TIME and TO_TIME
+denote the times between which the route is taken.
+<br>
+The <b>output</b> map contains the points on the positions of used
+stops. If a subroute is taken between two stops then a line segment
+is added between two corresponding points. Finally, instead of
+straight line segment, the actual paths of routes can be given in <b>
+paths</b> layer. If this parameter is used then each line in the
+input map must contain identificators as category numbers of all
+routes passing through the line. The module then finds the path
+between two stops and writes this path instead. In case of walking
+from one stop to another, straight line between the stops is used.
<h2>NOTES</h2>
-Timetables are stored in a table linked to the given <b>layer</b> of the
-<b>input</b> map. Timetable consists of routes and each route is just a
-sequence of stops with specified arrival times. If two sequences of stops
-differ only in times then they still correspond to two routes. For
-example, if there is a bus line that leaves every 20 minutes and follow
-exactly the same path every time then there still needs to be a separate
-route for every time. For each stop (given by the category number of the
-point) the table storing information about the routes must contain the
-list of all routes stopping at the stop(given by route identificators)
-together with arrival times. That is, the table must contain three
-columns: stop - which is the key of the table, <b>route_id</b> and
-<b>stop_time</b> where each triple corresponds to a route arriving to a
-stop and a certain time. For example, a valid table might look as follows:
+Timetables are stored in a table linked to the given <b>layer</b> of
+the <b>input</b> map. Timetable consists of routes and each route is
+just a sequence of stops with specified arrival times. If two
+sequences of stops differ only in times then they still correspond
+to two routes. For example, if there is a bus line that leaves every
+20 minutes and follow exactly the same path every time then there
+still needs to be a separate route for every time. For each stop
+(given by the category number of the point) the table storing
+information about the routes must contain the list of all routes
+stopping at the stop(given by route identificators) together with
+arrival times. That is, the table must contain three columns: stop -
+which is the key of the table, <b>route_id</b> and <b>stop_time</b>
+where each triple corresponds to a route arriving to a stop and a
+certain time. For example, a valid table might look as
+follows:
<div class="code"><pre>
cat|route_id|stop_time
100|5|0
@@ -97,41 +104,44 @@
300|35|37
100|35|50
</pre></div>
-Note that <b>stop_time</b> is an integer and so you can use any units and
-offest to specify arrival times.<br>
-Also, walking connections between stops can be given by a table linked to
-<b>walking</b> layer of the <b>input</b> map. If this parameter is -1
-then walking between stops is not allowed. The table must contain three
-columns: stop - which is the key of the table, <b>to_stop</b> and
-<b>length</b>. A record in the table says that it takes <b>length</b>
-units of time to walk from stop to <b>to_stop</b>. The following is a
-valid table:
+Note that <b>stop_time</b> is an integer and so you can use any
+units and offest to specify arrival times.<br> Also, walking
+connections between stops can be given by a table linked to <b>
+walking</b> layer of the <b>input</b> map. If this parameter is -1
+then walking between stops is not allowed. The table must contain
+three columns: stop - which is the key of the table, <b>to_stop</b>
+and <b>length</b>. A record in the table says that it takes <b>length
+</b> units of time to walk from stop to <b>to_stop</b>. The
+following is a valid table:
<div class="code"><pre>
cat|length|to_stop
250|2|300
</pre></div>
-Beware that this only means that it is possible to walk from stop 250 to
-stop 300 but not the other way round.
+Beware that this only means that it is possible to walk from stop
+250 to stop 300 but not the other way round.
<h2>EXAMPLES</h2>
-To find a path from stop with identificator 130 to stop with category 300,
-starting at time 0, with one time unit for change, maximum of 5 changes
-and with walking not considered a change of route, we use the following
-command:
+To find a path from stop with identificator 130 to stop with
+category 300, starting at time 0, with one time unit for change,
+maximum of 5 changes and with walking not considered a change of
+route, we use the following command:
<div class="code"><pre>
-echo "47 130 300 0 1 5 0" | v.net.timetable input=buses output=path layer=5 walking=6 path=7
+echo "47 130 300 0 1 5 0" | v.net.timetable \
+ input=buses output=path layer=5 walking=6 path=7
</pre></div>
-If on the other, hand we know the coordinates of the places then the
-following command might be used
+If, on the other hand, we know the coordinates of the places then the
+following command might be used:
<div class="code"><pre>
-echo "47 10.31 54.31 90.21 28.21 0 1 5 0" | v.net.timetable input=buses output=path layer=5 walking=6 path=7
+echo "47 10.31 54.31 90.21 28.21 0 1 5 0" | v.net.timetable \
+ input=buses output=path layer=5 walking=6 path=7
</pre></div>
<h2>SEE ALSO</h2>
<em>
+<a href="v.net.html">v.net</a>,
<a href="v.net.path.html">v.net.path</a>,
<a href="v.net.distance.html">v.net.distance</a>
</em>
Modified: grass/trunk/vector/v.net.visibility/v.net.visibility.html
===================================================================
--- grass/trunk/vector/v.net.visibility/v.net.visibility.html 2013-05-23 17:04:18 UTC (rev 56388)
+++ grass/trunk/vector/v.net.visibility/v.net.visibility.html 2013-05-23 19:59:24 UTC (rev 56389)
@@ -11,11 +11,11 @@
the visibility graph and from it compute the shortest path using
<em>v.net.path</em> or <em>d.path</em>.
-
-<b>IMPORTANT : the algorithm doesn't work well with intersecting lines
+<b>IMPORTANT: the algorithm doesn't work well with intersecting lines
(that includes overlapping)</b>
-<p>If you compute a shortest path after computing the visibility graph you
+<p>
+If you compute a shortest path after computing the visibility graph you
will notice that this path might go through a vertix of a line. If this
is not wanted you might to run the map through <em>v.buffer</em> first
whith a small value. Example:
@@ -24,26 +24,30 @@
v.buffer input=map output=bufferedmap buffer=1 type=point,line,area,boundary
</pre></div>
-<p>The first argument is the input map. It supports lines, boudaries (so areas)
-and points. For the algorithm to work lines and boundaries must not be
-intersecting (that includes overlapping).
+<p>
+The first argument is the input map. It supports lines, boudaries
+(so areas) and points. For the algorithm to work lines and
+boundaries must not be intersecting (that includes overlapping).
+<br>
The result map containing the visibility graph is given in the output map.
-If you need to add additional points to compute a shortest path between them
-afterwards you can use the <em>coordinate</em> parameter.
+If you need to add additional points to compute a shortest path
+between them afterwards you can use the <em>coordinate</em> parameter.
<div class="code"><pre>
coordinate=25556200,6686400,25556400,6686600
</pre></div>
-where 25556200,6686400 are the coordinate of the first point and 25556400,6686600
-are the coordinates of the second point. Of course you can give as many points as
-you want. They will be added to the visibility graph and edges from them will be
-computed. You can always add those points after computing the visibility graph.
-Simply use the <em>vis</em> parameter. The input will be the original vector map,
-the vis will be the computed visibility graph and the output the new visibility
-graph which will be the vis + the new points given with coordinate (edges will
-be computed as well).
+where 25556200,6686400 are the coordinate of the first point and
+25556400,6686600 are the coordinates of the second point. Of course
+you can give as many points as you want. They will be added to the
+visibility graph and edges from them will be computed. You can
+always add those points after computing the visibility graph. Simply
+use the <em>vis</em> parameter. The input will be the original
+vector map, the vis will be the computed visibility graph and the
+output the new visibility graph which will be the vis + the new
+points given with coordinate (edges will be computed as well).
<div class="code"><pre>
-v.net.visibility input=map vis=vis_map output=new_vis_map coordinate=25556200,6686400,25556400,6686600
+v.net.visibility input=map vis=vis_map output=new_vis_map \
+ coordinate=25556200,6686400,25556400,6686600
</pre></div>
<h2>EXAMPLE 1</h2>
@@ -68,7 +72,7 @@
An example on how to use the coordinate parameter. This will compute the
visibility graph of the vector map lines with the point 2555678,6686343
<div class="code"><pre>
-v.net.visibility input=lines output=graph coordinate=2555678,6686343<br>
+v.net.visibility input=lines output=graph coordinate=2555678,6686343
d.vect graph
d.vect lines col=red
</pre></div>
@@ -81,7 +85,8 @@
v.net.visibility input=lines output=graph
d.vect graph
d.vect lines col=red
-v.net.visibility input=lines vis=graph output=new_graph coordinate=2555678,6686343
+v.net.visibility input=lines vis=graph output=new_graph \
+ coordinate=2555678,6686343
d.erase
d.vect new_graph
d.vect lines col=red
@@ -99,10 +104,10 @@
</pre></div>
<h2>KNOWN BUGS</h2>
-In some cases when 3 points or nodes are collinear, some wrong edges are added.
-This happens only really rarly and shouldn't be a big problem.
-When two points have the exact same x coordinate and are visible, some wrong
-edges are added.
+In some cases when 3 points or nodes are collinear, some wrong edges
+are added. This happens only really rarly and shouldn't be a big
+problem. When two points have the exact same x coordinate and are
+visible, some wrong edges are added.
<h2>SEE ALSO</h2>
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