[GRASS-user] V.voronoi

[Sampson, David]

Hey folks,

Looking for a some ideas and help.

I am ttrying to use the v.voronoi (in wingrass) tool and it is
perplexing me with the results I am getting. Here is the scenario.

I am trying to anaylise the spatial distribution of road intersections.
I started with a road network file from Statistics Canada, and clipped
out the roads of the city of Ottawa for my subset. I created a new
vector containing only the nodes of the Ottawa network. The resulting
vector has the following basic stats
=========
Type of Map:  vector (level: 2)
|
 |
|
 |   Number of points:       48156           Number of areas:      0
|
 |   Number of lines:        0               Number of islands:    0
|
 |   Number of boundaries:   0               Number of faces:      0
|
 |   Number of centroids:    0               Number of kernels:    0
|
 |
|
 |   Map is 3D:              0
|
 |   Number of dblinks:      2
===========

The nodes represent both road terminations and intersections.

I am new to using Voronoi charts but when I run the v.voronoi script I
expect it to create a polygon for each node.

Instead when I run the basic stats on the new Veronoi vector I get:

=============
 Type of Map:  vector (level: 2)
|
 |
|
 |   Number of points:       0               Number of areas:      1
|
 |   Number of lines:        0               Number of islands:    1
|
 |   Number of boundaries:   4               Number of faces:      0
|
 |   Number of centroids:    0               Number of kernels:    0
|
 |
|
 |   Map is 3D:              0
|
 |   Number of dblinks:      1        
=============

I get a rectangular shape that is located just north of ONE of the nodes
in the coverage. As I zoom out some other nodes apear surounding
rectangualr shape...  The manual doesn't shed light on my situation.

Any help, experieince or knowledge would be great.

Cheers
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