Revision as of 18:05, 12 August 2008

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). Both directions are supported, network modules provide parameters to assign attribute columns to the forward and backward direction.

• see the vector map processing and network analysis help page

Shortest path routing

• see the v.net.path module 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.