Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
v.net.allpairs(1)	    GRASS GIS User's Manual	     v.net.allpairs(1)

NAME
       v.net.allpairs  - Computes the shortest path between all	pairs of nodes
       in the network.

KEYWORDS
       vector, network,	shortest path

SYNOPSIS
       v.net.allpairs
       v.net.allpairs --help
       v.net.allpairs	[-g]   input=name   output=name	    [arc_layer=string]
       [node_layer=string]     [cats=range]	[where=sql_query]    [arc_col-
       umn=name]	[arc_backward_column=name]	  [node_column=string]
       [--overwrite]  [--help]	[--verbose]  [--quiet]	[--ui]

   Flags:
       -g
	   Use geodesic	calculation for	longitude-latitude locations

       --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=nameA [required]
	   Name	of input vector	map
	   Or data source for direct OGR access

       output=nameA [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 ac-
	   cess	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 ac-
	   cess	this is	the layer name.
	   Default: 2

       cats=range
	   Category values
	   Example: 1,3,7-9,13

       where=sql_query
	   WHERE conditions of SQL statement without 'where' keyword
	   Example: income < 1000 and population >= 10000

       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)

DESCRIPTION
       v.net.allpairs  computes	 the  shortest path between each selected node
       and all other selected nodes. The output	is a vector with the  selected
       nodes and the shortest paths.

NOTES
       An  attribute table is created and linked to layer arc_layer. The table
       contains	four columns: cat, from_cat, to_cat, cost.  Each cat entry de-
       notes  the  category  of	 the shortest path from	the node with category
       from_cat	to the node with category to_cat. If points are	 specified  by
       cats,  layer  or	where parameters then the table	is filled only for the
       selected	points.
       If arc_backward_column is not given then	then the same costs  are  used
       for forward and backward	arcs.

EXAMPLE
       Find  shortest path along roads from selected archsites (Spearfish sam-
       ple dataset):
       # prepare network: connect archsites to roads with threshold 200
       v.net input=roads@PERMANENT points=archsites@PERMANENT \
       output=roads_net	operation=connect thresh=200
       # verify	result
       v.category input=roads_net option=report
       # only lines should have	a category in layer 1
       # only points should have a category in layer 2
       # shortest path between all points with categories 1 - 5	in layer 2
       v.net.allpairs input=roads_net cats=1-5 out=roads_net_all
       v.db.select roads_net_all
       Result in matrix	form:
       from\to	 1	   3	     4	       5
       1    0	      18820.386	17206.651 17373.274
       3    18820.386 0		1739.079  9040.575
       4    17206.651 1739.079	0	  7426.84
       5    17373.274 9040.575	7426.84	       0

SEE ALSO
	v.net.path, v.net.distance

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

SOURCE CODE
       Available at: v.net.allpairs source code	(history)

       Main index | Vector index | Topics index	| Keywords index  |  Graphical
       index | Full index

       A(C) 2003-2020 GRASS Development	Team, GRASS GIS	7.8.3 Reference	Manual

GRASS 7.8.3						     v.net.allpairs(1)

NAME | KEYWORDS | SYNOPSIS | DESCRIPTION | NOTES | EXAMPLE | SEE ALSO | AUTHORS | SOURCE CODE

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=v.net.allpairs&sektion=1&manpath=FreeBSD+12.2-RELEASE+and+Ports>

home | help