Difference between revisions of "Vector network analysis"

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(say how to see vector directions)
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* Iso-distances (from centers): {{cmd|v.net.iso}}
 
* Iso-distances (from centers): {{cmd|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.
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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  {{cmd|d.vect}} (set display=dir).
  
 
* see the {{cmd|vectorintro}} "vector map processing and network analysis" help page
 
* see the {{cmd|vectorintro}} "vector map processing and network analysis" help page

Revision as of 09:50, 14 January 2009

Vector network analysis

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

The following algorithms are implemented:

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

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.