Vector network analysis

Vector network analysis

GRASS provides support for vector network analysis using the DGlib Directed Graph Library.

The following algorithms are implemented:

• Vector maintenance: v.net
• Shortest path: d.path and v.net.path
• Traveling salesman (round trip): v.net.salesman
• Allocation of sources (create subnetworks, e.g. police station zones): v.net.alloc
• Minimum Steiner trees (star-like connections, e.g. broadband cable connections): v.net.steiner
• Iso-distances (from centers): v.net.iso

Vector directions are defined by the digitizing direction (a-->--b). You can navigate either omnidirectionally or differently in each directions as both directions are supported. Network modules provide parameters to assign attribute columns to the forward and backward direction. To see how a vector is directed, use the "display" parameter of d.vect (set display=dir).

• see the vectorintro "vector map processing and network analysis" help page

Shortest path routing

• see the v.net.path and d.path help pages

New ideas

• Vector network analysis ideas (please help to realize)

Screenshots

• more screenshots from the GRASS website

v.net.iso - Split net to bands between cost isolines (direction from centre). Costs of centre node are used in calculation.

v.net.alloc - Allocates subnets for nearest centres (direction from centre). Costs of centre node are used in calculation.

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