## DESCRIPTION

d.path enables shortest path vector networking. Costs may be either line lengths, or attributes saved in a database table. 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.

## NOTE

The user needs to display a vector map before using d.path. If no graphics monitor is open, a file `map.png` is generated in the current directory.

The 'from' and 'to' points are entered by mouse into the map displayed in the GRASS monitor, or if the coordinates option is used they can be specified non-interactively. The actions bound to the mouse buttons are described in the terminal window when running the command.

To calculate shortest path non-interactively and save the path to a new vector map, use the v.net.path module.

## EXAMPLES

Interactive shortest path routing on road network (North Carolina sample dataset):

    g.region vector=roadsmajor -p
    d.vect roadsmajor
    d.path roadsmajor coordinates=668646.15,224447.16,668348.83,235894.02

Non-interactive shortest path routing on road network (North Carolina sample dataset):

    d.path -b roadsmajor coordinates=668646.15,224447.16,668348.83,235894.02

## SEE ALSO

v.net.path

## AUTHOR

Radim Blazek, ITC-Irst, Trento, Italy

Last changed: $Date$