## DESCRIPTION

v.net.iso splits net to bands between cost isolines (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

Nodes must be on the isolines.

Center nodes have to be assigned to vector nodes. Nodes and arcs can be closed using cost = -1.

## EXAMPLE

Subdivision of a network into areas:
The map must contain at least one center (point) on the vector network which can be patched into with v.patch.

    v.net.iso input=streets output=isomap ccats=1 costs=1000,2000,5000

that should cut network to 4 categories:

    cat | distance from point
    1          0 - 1000
    2       1000 - 2000
    3       2000 - 5000
    4            > 5000

To see the result, run for example:

    d.vect isomap col=green  cats=1
    d.vect isomap col=yellow cats=2
    d.vect isomap col=orange cats=3
    d.vect isomap col=red    cats=4

## SEE ALSO

d.path, v.net.alloc, v.net.salesman, v.net.steiner, v.patch

## AUTHOR

Radim Blazek, ITC-Irst, Trento, Italy

Last changed: $Date: 2004/12/01 08:28:48 $