[GRASS-user] connect points to end points via v.net

[Christopher Mire]

On Thu, Jan 22, 2009 at 10:00 AM, Moritz Lennert <
mlennert at club.worldonline.be> wrote:

> On 21/01/09 16:33, Christopher Mire wrote:
>
>> Hello, I have a problem that I am considering doing some manual coding
>> for,
>> but thought I would check here for easier way first.  I'm new to grass, so
>> there
>> are still alot of things I don't know.
>>
>> Basically I have this huge vector map which
>> is mostly connected.  Problem is that there are a bunch of intersections
>> of lines
>> that dont actually connected together, due to way data was put together.
>>  Instead I
>> have another vector map which is just a bunch of points.  Usually these
>> points all
>> correspond to one of these disconnected intersections.  What I want to do
>> is
>> connect each point to all of the unconnected end points within some
>> threshold
>> distance.  My plan is to use v.net.path on network, but I need to have it
>> all
>> connected so this is why I am doing this.  I know there is v.net <
>> http://v.net>, but this
>> connects points to a line, where as I only want to connected points to the
>> end points of a line, or even connecting to line, but only if endpoint of
>> line is
>> within threshold.
>>
>> I was thinking about modifying v.net <http://v.net> to have option on
>> what to connect to, to
>> specify option to only connect to endpoints instead of anywhere on line.
>>  Does
>> this sound reasonable, or is there way to get this behavior another way?
>>
>
> Not sure I understand exactly what you want to do, but I have the feeling
> that v.edit should help you do the job.
>
> Moritz
>

Hmm, basically there are a bunch connected lines in this vector map.  In
certain regions of this map
the lines don't actually intersect, but just really close to each other.
Luckily I happen to have ,roughly,
the coordinate of each of these intersections where the points don't
actually touch.  What I want to do
is use this coordinate to connect all the close endpoints to it, therefore
completing the connections in
graph so I am able to traverse with other GRASS modules.  By endpoints, I
mean I don't want to
connect the point to the closest line, but rather the closest endpoint of a
line, if within threshold.  This
is because there might be lines passing through intersection which I don't
want to connect to, but
rather only the lines which end there.

I had tried v.edit snap tool, but I ended up just merging lines together,
which I don't want.
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