faq 107845803

Why does network cleaner keep deleting my links?

by Celeste Manu on 2017-02-14 18:32:13

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I have a simple MATSIM network created in JOSM. Whenever I convert that OSM that I made into a MATSim network file (xml) in JOSM, or try to clean the network, it gets rid of some links in the network. I need to clean my network because when I run this network in MATSim with a plan from one corner to another corner, I get the error: No route found from node -314 to node -52, which means my network is disconnected in come way. 

When i put that .osm into the networkCleaner class in MATSim: 

java -Xmx512m -cp networkEditor-0.8.1.jar:matsim-0.8.1.jar org.matsim.contrib.networkEditor.run.RunNetworkEditor

It gets rid of the links. 

When I convert my network in JOSM, it gets rid of critical links. Here is my OSM i created in JOSM:

Here it is again after I go to Matsim>Convert to matsim layer

As you can see some links have disappeared - links that are joined to the corner nodes.

I have tried combining ways, joining node to way, merging, joining overlapping areas, and none of these result in my OSM being converted to a matsim xml network file with the same network layout. Why do my links keep disappearing when I clean or convert it and how can I  get them to stay?
 

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Comments: 2

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Re: Why does network cleaner keep deleting my links?

by Johan W. Joubert on 2017-02-15 05:09:12

Hi Celeste, the only reason the NetworkCleaner should/would remove links is if they are evaluated as dead ends, or cannot be reached. That is, there is somewhere a problem with the connectivity in the osm layer you created in JOSM. And that is evident from the colouring of the nodes. Those that do seem connected turns up light blue/turquoise... and the others unfilled yellow. These latter nodes are then also the ones that do not appear in your final network. And it may, unfortunately, not be that simple to find. It may be a small non-connection, and the cleaner would then work recursively backward and remove links until it finds a properly connected graph again.

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Re: Why does network cleaner keep deleting my links?

by Nico Kuehnel on 2017-02-15 13:23:27

Hi Celeste,

this obviously happens because the converting algorithm in the josm plugin detects nodes that are not essentially needed for the simulation network graph. Since a way in openstreetmap can hold more than two nodes the converter will only connect those nodes of a way that are essential - e.g. a crossing with another way. All the other nodes are filtered out by default. 

If you need a topologically identical network of the drawn ways you have to activate the "Keep Paths" option in the plugins preferences panel in JOSM. This will make the converter keep all nodes, building a topologically exact copy, resulting in a more complex network