## NAME

v.net.alloc

## DESCRIPTION

v.net.alloc allocates subnets for nearest centres (direction from centre). Centre node must be opened (costs >= 0). Costs of centre node are used in calculation. Supported are cost assignments for both arcs and nodes, and also different in both directions of a vector line. For areas cost will be calculated along boundary lines.

## NOTES

Center nodes have to be assigned to vector nodes using v.digit or added from other map(s). Nodes and arcs can be closed using cost = -1.

## EXAMPLES

Example 1: Calculating subnets for 3 centre nodes using distances

    #Spearfish

    # centre nodes:
    echo "591235.5|4926306.62|1
    596591.8|4917042.5|2
    602722.9|4923544.2|3" | v.in.ascii out=centrenodes

    g.copy vect=roads,myroads

    #connect points to network
    v.net myroads points=centrenodes out=myroads_net op=connect thresh=200

    # view map
    g.region vect=myroads_net
    d.mon x0
    d.vect myroads_net
    d.vect myroads_net col=red icon=basic/triangle fcol=green size=12 layer=2

    # allocate, specifying range of center cats (easier to catch all):
    v.net.alloc myroads_net out=myroads_net_alloc ccats=1-100000 nlayer=2

    # report categories
    v.category myroads_net_alloc option=report

    # the result has to be selected by category number of the relevant node:
    d.vect myroads_net_alloc cat=1 col=red
    d.vect myroads_net_alloc cat=2 col=green
    d.vect myroads_net_alloc cat=3 col=yellow
    d.vect myroads_net col=red icon=basic/triangle fcol=green size=12 layer=2

Example 2: Calculating subnets for 7 centre nodes using cost assigned to vector length

    v.net.alloc in=vectmap out=vectmap.alloc ccats=1-7

Example 3: Calculating subnets for 7 centre nodes using cost assignments in both directions

    v.net.alloc in=vectmap afcol=INDEX abcol=INDEXBACK out=vectmap.alloc ccats=1-7

## SEE ALSO

d.path, v.net, v.net.iso, v.net.path, v.net.steiner, v.net.salesman

## AUTHOR

Radim Blazek, ITC-Irst, Trento, Italy

Last changed: $Date: 2009-03-05 00:00:42 +0100 (Thu, 05 Mar 2009) $

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