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v.net.components - Computes strongly and weakly connected components in the network.
vector, network, components
v.net.components [-a] input=name [layer=integer] output=name method=string [--overwrite] [--verbose] [--quiet]
- Add points on nodes
- Allow output files to overwrite existing files
- Verbose module output
- Quiet module output
- Name of input vector map
- Layer number
- A single vector map can be connected to multiple database tables. This number determines which table to use.
- Default: 1
- Name for output vector map
- Type of components
- Options: weak,strong
- weak: Weakly connected components
- strong: Strongly connected components
v.net.components computes the weakly and strongly connected
components in a network.
Two nodes, u and v are in the same strongly
connected component if there are directed paths from u to
v and from v to u. The nodes are in the
same weakly connected component if, ignoring orientation of the
edges, there is a path between them.
The type of components is specified by method parameter.
v.net.components creates a table and links it to the given layer.
This table contains only two integer columns: cat and comp
. 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 -a 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
Any road network should form a single strongly connected component.
Otherwise, it is impossible to travel between some places.
v.net.components input=roads output=roads_components method=strong
Daniel Bundala, Google Summer of Code 2009, Student
Wolf Bergenheim, Mentor
Last changed: $Date: 2013-05-23 13:01:55 -0700 (Thu, 23 May 2013) $
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