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 alayer=string nlayer=string [afcolumn=name] [abcolumn=name] output=name [ncolumn=name] [set1_cats=range] [set1_where=sql_query] [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 [required]
- Name of input vector map
- Or data source for direct OGR access
- alayer=string [required]
- Layer number or name
- Arc layer
- Default: 1
- nlayer=string [required]
- Layer number or name
- Node layer
- Default: 2
- afcolumn=name
- Arc forward/both direction(s) cost column (number)
- abcolumn=name
- Arc backward direction cost column (number)
- output=name [required]
- Name for output vector map
- ncolumn=name
- Node cost column (number)
- 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 < 1000 and inhab >= 10000
- set2_cats=range
- Category values
- Set2 category values
- set2_where=sql_query
- Set2 WHERE conditions of SQL statement without 'where' keyword
- Example: income < 1000 and inhab >= 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.flow,
v.net.bridge
AUTHORS
Daniel Bundala, Google Summer of Code 2009, Student
Wolf Bergenheim, Mentor
Last changed: $Date: 2011-11-08 13:24:20 -0800 (Tue, 08 Nov 2011) $
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