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, 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 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?
Thanks.
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
On Thu, Jan 22, 2009 at 10:00 AM, Moritz Lennert <mlennert@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.