Difference between revisions of "Vector network analysis"

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GRASS provides support for vector network analysis using the [http://trac.osgeo.org/grass/browser/grass/trunk/lib/vector/dglib/ DGlib] Directed Graph Library.
 
GRASS provides support for vector network analysis using the [http://trac.osgeo.org/grass/browser/grass/trunk/lib/vector/dglib/ DGlib] Directed Graph Library.
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== Implemented algorithms ==
  
 
The following algorithms are implemented (GRASS 6.5+):
 
The following algorithms are implemented (GRASS 6.5+):
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* see the {{cmd|vectorintro}} "vector map processing and network analysis" help page
 
* see the {{cmd|vectorintro}} "vector map processing and network analysis" help page
  
== Shortest path routing ==
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== Example: Shortest path routing ==
  
 
* see the {{cmd|v.net.path}} and {{cmd|d.path}} help pages
 
* see the {{cmd|v.net.path}} and {{cmd|d.path}} help pages

Revision as of 14:01, 10 April 2010

Vector network analysis

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

Implemented algorithms

The following algorithms are implemented (GRASS 6.5+):

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

Example: Shortest path routing

New ideas

Screenshots


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.

See also