NAME¶

v.net.connectivity - Computes vertex connectivity between two sets of nodes in the network.

KEYWORDS¶

vector, network, connectivity

SYNOPSIS¶

v.net.connectivity v.net.connectivity help v.net.connectivity input=name [layer=integer] output= name [ncolumn=name] [set1_layer=integer] [ set1_cats=range] [set1_where= sql_query] [set2_layer=integer] [set2_cats= range] [set2_where=sql_query] [--overwrite] [-- verbose] [--quiet]

Flags:¶

--overwrite

 

Allow output files to overwrite existing files

--verbose

 

Verbose module output

--quiet

 

Quiet module output

Parameters:¶

input=name

 

Name of input 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

output=name

 

Name for output vector map

ncolumn=name

 

Name of node capacity column

set1_layer=integer

 

Set1 layer number or name

 

A single vector map can be connected to multiple database tables. This number determines which table to use.

 

Default: 1

set1_cats=range

 

Set1 category values

 

Example: 1,3,7-9,13

set1_where=sql_query

 

Set1 WHERE conditions of SQL statement without 'where' keyword

 

Example: income = 10000

set2_layer=integer

 

Layer number

 

Set2 layer number or name

 

Default: 1

set2_cats=range

 

Category values

 

Set2 category values

set2_where=sql_query

 

Set2 WHERE conditions of SQL statement without 'where' keyword

 

Example: income = 10000

DESCRIPTION¶

v.net.connectivity computes vertex connectivity between two sets, i.e. the minimum number of vertices whose removal would separate two given sets.

NOTES¶

Two sets ( set1 and set2) are specified by respective layer, where and cats parameters. Similarly to v.net.flow module, capacities of nodes can be given by ncolumn option. v.net.connectivity finds the set of nodes of minimum total capacitiy separating the two given sets and outputs map containing points on the positions of these nodes. Default capacity, which is used when no column is specified, is one.

EXAMPLES¶

The following command finds the minimum number of intersections separating roads on the left bank from roads on the right bank. v.net.connectivity input=roads output=roads_conn set1_where="bank=left" \
set2_where="bank=right" v.net.connectivity input=airtraffic output=connectivity \
set1_where="name=JFK" set2_where="name=Heathrow" ncolumn=capacity

SEE ALSO¶

v.net, v.net.flow, v.net.bridge

AUTHORS¶

Daniel Bundala, Google Summer of Code 2009, Student Wolf Bergenheim, Mentor Last changed: $Date: 2013-05-23 22:01:55 +0200 (Thu, 23 May 2013) $ Full index © 2003-2014 GRASS Development Team