GRASS logo

Note: A new GRASS GIS stable version has been released: GRASS GIS 7, available here. And see the new manual page here

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=integer] [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
output=name
Name for output vector map
layer=integer
Layer number
A single vector map can be connected to multiple database tables. This number determines which table to use.
Default: 1
accol=name
Name of Arc cost column

DESCRIPTION

v.net.spanningtree finds the minimum spanning tree in a network.

NOTES

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, v.net.spanningtree 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. 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, v.net.steiner

AUTHORS

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) $


Main index - vector index - Full index

© 2003-2016 GRASS Development Team