GRASS GIS manual: d.path

Note: A new GRASS GIS stable version has been released: GRASS GIS 7.8, available here.
Updated manual page: here

NAME

d.path - Finds shortest path for selected starting and ending node.

KEYWORDS

display, network, shortest path

SYNOPSIS

d.path

d.path --help

d.path [-gb] map=name [arc_type=string[,string,...]] coordinates=x1,y1,x2,y2 [arc_layer=string] [node_layer=string] [arc_column=string] [arc_backward_column=string] [node_column=string] [color=string] [highlight_color=string] [bgcolor=string] [--help] [--verbose] [--quiet] [--ui]

Flags:

-g: Use geodesic calculation for longitude-latitude locations
-b: Render bold lines
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

map=name [required]: Name of vector map; Or data source for direct OGR access
arc_type=string[,string,...]: Arc type; Options: line, boundary; Default: line,boundary
coordinates=x1,y1,x2,y2 [required]: Starting and ending coordinates
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=string: Arc forward/both direction(s) cost column (number)
arc_backward_column=string: Arc backward direction cost column (number)
node_column=string: Node cost column
color=string: Original line color; Default: black
highlight_color=string: Highlight color; Default: red
bgcolor=string: Background color; Default: white

DESCRIPTION
NOTE
EXAMPLES
SEE ALSO
AUTHOR

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

AUTHOR

Radim Blazek, ITC-Irst, Trento, Italy

Last changed: $Date$

SOURCE CODE

Available at: d.path source code (history)