[GRASS-user] Checking and fixing roads for network analysis

[Daniel Victoria]

Hi List,

I'll need to perform some network analysis and right now I'm trying to see
if my roads map is all good. I know that there are some clearly isolated
areas on my roads network but I'd like to identify and fix the less obvious
ones.

Here is what I did:
1) Import road lines (v.in.ogr)
2) Clean the topology with snap tool, thresh=0.0001 (it's a latlong
location)
2) Create network (v.net using the nodes option --not sure if that was the
correct option)
3) Ran v.net.components to find the weakly connected components, not
setting any cost columns
4) Color roads lines according to the component number

By doing that I could spot the lines that were clearly disconnected
(net_components_unlink.png).
But I also found some lines that where disconnected even thou there are
nodes (red squares) linking them (apparently) -
net_components_pseudo_link.png

Should I increase my snapping threshold?
How can I see if my nodes are endnodes or located between two lines?

Thanks
Daniel
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