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Hi,

 

Since, I work with spatial data and more into ESRI formats, so I come along with different problems with the same format type, and again, I am stuck with a new problem here. Though, its a bit difficult to explain, yet, let me try:

 

I have a Road Network with Polyline geometry. Each Road Network Element (line segment) has a start and an end node. If we split the line at junctions/intersections and add a point to each start an end node to each Line Segment, there will be a certain number of overlapping nodes (image below).

 

My question is will I be able to extract the count of nodes at every junction?

 

Pl feel free to ask queries if I am not able to communicate properly.

 

Use a SpatialRelator with the same data as Requestor and Supplier. You will then get a _related_candidates with the number of overlapping nodes
@hellblazer
Hi

 

 

Take a look at the TopologyBuilder. Using the output lines, count the number of uniquely occurring values in from_node and to_node, this count will give you the number of connections for each node ID.

 

 

David
You could also use a matcher to find overlapping nodes, outputting via
the singlematched output port and setting the "match count attribute on
singlematched output" will give you a count of nodes at each location.
Hi,

 

Thanks everyone for the advices and help!! :)

 

 

@sigtill Though, i did try your method, but I guess I was making a very minute mistake somewhere. I tried using Intersector (for generating nodes out of lines) and SpatialRelator (to obtain the Valance counts in _related_candidates).

 

 

@david_r I did try TopologyBuilder and found all my _from_node and _to_node unique. I am not sure how I can move ahead with this.

 

 

@egomm I tried using Matcher but didn't find the solution. Can you explain a biy more

 

 

 

Apart from this, I tried using Intersector (to get the nodes and to split the line at junctions) and PointOnLineOverlay. Under the _overlap, I got the desired result. Yet, it is under testing.

 

Use a LineOnLine overlayer to split lines into segments where they
meet/cross other lines, create points at start and end points of the
resulting line output, then the matcher to count how many points are in the same location
Hi

 

 

Using the TopologyBuilder works for me. I could even simplify it a bit using only the output nodes and then counting the elements in the _node_angle{} list:

 

 

 

 

Here's the relevant part of the workspace:

 

 

 

 

David

 

-Topology builder, ie. like David shows.

 

-Network to create from to's. Compare etc. like below.

 

 

-Or old style: vertex-extraction (start and end)

 

Listbuilder grouped by line_id.

 

Then unconditional merger.

 

Then compare end_node to start_node. (x,y comparison). Count em.

 

 

Wichever you use, it involves list-functions.

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