
NAME
v.net.spanningtree - Computes minimum spanning tree for the network.
KEYWORDS
vector, network, spanning tree
SYNOPSIS
v.net.spanningtree
v.net.spanningtree help
v.net.spanningtree [-g] input=name output=name layer=string [accol=name] [--overwrite] [--verbose] [--quiet]
Flags:
- -g
- Use geodesic calculation for longitude-latitude locations
- --overwrite
- Allow output files to overwrite existing files
- --verbose
- Verbose module output
- --quiet
- Quiet module output
Parameters:
- input=name
- Name of input vector map
- Data source for direct OGR access
- output=name
- Name for output vector map
- layer=string
- Layer number or name
- A single vector map can be connected to multiple database tables. This number determines which table to use. Layer name for direct OGR access.
- Default: 1
- accol=name
- Name of Arc cost column
DESCRIPTION
v.net.spanningtree find the minimum spanning tree in a network.
NOTES
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, module does not compute spanning tree but a spanning forest. As the name suggests spanning tree is a tree. That is, it contains no cycles and if a component has N nodes that the tree has N-1 edges and connected all nodes. Accol is used to specify the costs of the edges. The output consists of the edges in the spanning tree.
EXAMPLES
Find cheapest set of pipelines connecting all nodes.
v.net.spanningtree input=projected_pipelines output=spanningtree accol=cost
SEE ALSO
v.net.steiner
AUTHORS
Daniel Bundala, Google Summer of Code 2009, Student
Wolf Bergenheim, Mentor
Last changed: $Date: 2010-04-10 10:01:48 -0700 (Sat, 10 Apr 2010) $
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