NAME

v.net.bridge - Computes bridges and articulation points in the network.

KEYWORDS

vector, network, articulation points

SYNOPSIS

v.net.bridge
v.net.bridge --help
v.net.bridge input=name output=name [arc_layer=string] [node_layer=string] [arc_column=name] [arc_backward_column=name] [node_column=string] method=string [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

--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)
arc_backward_column=name: Arc backward direction cost column (number)
node_column=string: Node cost column (number)
method=string [required]: Feature type
Options: bridge, articulation
bridge: Finds bridges
articulation: Finds articulation points

DESCRIPTION

v.net.bridge finds bridges and articulation points in a network.

NOTES

Bridge in a network is an edge/line whose removal would disconnect the (sub-)network. A node is an articulation point if its removal would disconnect the (sub-)network. For more information and formal definitions check the wikipedia entries: bridge and articulation point.

The output of the module contains the selected features. For method=bridge, lines corresponding to bridges are copied from the input map to the output map. On the other hand, for method=articulation, points are created on the positions of articulation points.

In GRASS GIS, line is not always a single line segment. It might be, and often is, a sequence of line segments between two intersections. Also, articulation point is a standard graph theoretic terminology which is slightly misleading in GRASS. An articulation point in graph theory is an articulation node in GRASS terminology.

EXAMPLES

TBD

AUTHORS

Daniel Bundala, Google Summer of Code 2009, Student
Wolf Bergenheim, Mentor

SOURCE CODE

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