GRASS logo

Note: A new GRASS GIS stable version has been released: GRASS GIS 7. Go directly to the new manual page here

NAME - Computes bridges and articulation points in the network.


vector, network, articulation points

SYNOPSIS help input=name output=name [layer=integer] method=string [--overwrite] [--verbose] [--quiet]


Allow output files to overwrite existing files
Verbose module output
Quiet module output


Name of input vector map
Name for output vector map
Layer number
A single vector map can be connected to multiple database tables. This number determines which table to use.
Default: 1
Feature type
Options: bridge,articulation
bridge: Finds bridges
articulation: Finds articulation points

DESCRIPTION finds bridges and articulation points in a network.


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.



SEE ALSO, v.category,


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