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Note: This document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade, and read the current manual page.

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 [arc_layer=string] [node_layer=string] [arc_column=name] [node_column=name] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-g
Use geodesic calculation for longitude-latitude locations
--overwrite
Allow output files to overwrite existing files
--help
Print usage summary
--verbose
Verbose module output
--quiet
Quiet module output
--ui
Force launching GUI dialog

Parameters:

input=name [required]
Name of input vector map
Or data source for direct OGR access
output=name [required]
Name for output vector map
arc_layer=string
Arc layer
Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.
Default: 1
node_layer=string
Node layer
Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.
Default: 2
arc_column=name
Arc forward/both direction(s) cost column (number)
node_column=name
Node cost column (number)

Table of contents

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 an undirected network (same forward and backward costs). 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

SOURCE CODE

Available at: v.net.spanningtree source code (history)

Latest change: Mon Nov 18 20:15:32 2019 in commit: 1a1d107e4f6e1b846f9841c2c6fabf015c5f720d


Note: This document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade, and read the current manual page.

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