## 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

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