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I asked this question a while ago about a route in a multimodal network dataset not using all forms of transport available. While the answer worked at the time, I am now in a similar situation again.

My multimodal network dataset has three feature classes containing a single bus route, bus stops and streets. The bus route and streets have fields containing one way status and the amount of seconds it takes to traverse them. My data is basically the same as the tutorial data for ESRI's tutorial on multimodal datasets, except I have bus lines instead of metro lines.

I think my problem is with setting up the connectivity groups correctly. The bus route was created by tracing along the streets and splitting it at bus stops. The bus stops are snapped to the end points of each segment of the bus route, i.e. Stop 1 is snapped to the from_point of Segment 1 etc. The streets are not split at intersections.

In theory, a pedestrian should be able to walk from a side road into a main road to a bus stop, board a bus, travel along the route, exit the bus and continue walking around the streets. My connectivity settings are as follows:

connectivity groups

I have been using ESRI's tutorial as the basis for my dataset, but according to this:

For example, two edges created from two distinct source feature classes can connect if they are in the same connectivity group. If they are in separate connectivity groups, the edges won't connect unless they are joined by a junction that participates in both connectivity groups.

This seems to imply that I only need one connectivity group. I have tried solving for a route using both setups, but I have gotten an error each time. The analysis settings:

analysis settings

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What error are you getting? –  R.K. Nov 18 '12 at 20:48
    
It would also make it easier for us to troubleshoot if you can somehow post a sample dataset. An illustration would be most useful, too. –  R.K. Nov 18 '12 at 21:01
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1 Answer

This could be part of the problem

The streets are not split at intersections.

If they aren't split at intersections then

If they do not share any coincident endpoints or vertices, no connectivity policy will create a junction at the point of intersection. Street data for network datasets must be cleaned first so that either vertices or endpoints are present at all intended junctions.

So it would behave like the illustration below, which might not be what you're expecting. Streets that don't share vertices won't be connected.

enter image description here

Why do your ftr_roads have Any vertex connectivity by the way?

You might also want to read up about connectivity and designing the network datasets, too.

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The data is not very consistent - some of the roads are split at intersections, others not. They all at least have vertices where they cross though, and they are coincident at end points. I'm not sure why I chose any vertex - I read somewhere at some point if the lines are not all split where they cross then choosing any vertex is better. Anyway, once I changed the bus route connectivity to any vertex as well, and used only one connectivity group, the route analysis worked as expected. –  Arabella Nov 19 '12 at 3:31
    
After some more testing (different combinations of connectivity: Any Vertex/End Point/Honor, End Point/End Point/Override etc), the only connectivity settings which give a solution at all is setting the roads and the route to Any Vertex, and the bus stops to Override. Placing network locations along the roads and bus route with PedestrianTime as impedance yields the shortest route by using the bus between stops, and then walking along the roads where there is no bus. –  Arabella Nov 19 '12 at 6:51
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