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        [arc_layer=string]          [node_layer=string]
       [arc_column=name]       [arc_backward_column=name]      output=name     [node_column=name]
       [set1_cats=range]    [set1_where=sql_query]    [set2_cats=range]    [set2_where=sql_query]
       [--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

       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)

       output=name [required]
           Name for output vector map

       node_column=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 node_column 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" node_column=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: 2014-12-24 15:44:33 +0100 (Wed, 24 Dec 2014) $

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