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I have created a simple network to test hierarchy. But apparently I am missing something. I have created an attribute for my roads called hierarchy and given it values of 1 to 3. The network is set to use Hierarchy but it is apparently going through the shortest route not the hierarchy.

I am including a photo.

The red and yellow lines : hierarchy 1 The green lines: hierarchy level 2 the orange line: Hierarchy level 3

So in my photo I would imagine to go from point 1 to 2 , it should go through the red or yellow path but it goes through the orange with hierarchy 3. Am I missing something?enter image description hereenter image description hereenter image description here

! enter image description here

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Have you followed the guidelines on these pages?

http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//004700000057000000

http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//004700000020000000

"Using hierarchy by default

As long as the network dataset has a hierarchy attribute, you can set any network analysis layer you create to use the hierarchy by default. To change this setting, start ArcCatalog and open the Network Dataset Properties dialog box. Click the Attributes tab, right-click the hierarchy network attribute, then click Use By Default. You can also choose to enable hierarchies in ArcMap for each network analysis layer that you add by following these steps: open the Layer Properties dialog box for your network analysis layer, click the Analysis Settings tab, then click Use Hierarchy. Alternatively, you can perform a normal analysis by unchecking Use Hierarchy. Changing hierarchy ranges

To adjust the ranges that define the hierarchy attribute, see Modifying network attributes. Keep in mind, however, that if your network dataset is read-only, you won't be able to change the hierarchy ranges."

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Here is what I am giving you: enter image description here

  • yeas, I have read those resources several times and built this network several times. But the result is the same. – Mo Ask Oct 1 '14 at 17:47
  • ok can you include a photo of your settings? before you build the network. – I Heart Beats Oct 1 '14 at 17:48
  • sure, thank you for the help,I add the photos to the question. – Mo Ask Oct 1 '14 at 17:57
  • ok I have added photos to my answer above. Basically, when I set up mine, I had 3 .shp files (Highways, roads etc) for each road type and the analysis automatically established the hierarchy. I wonder if you could keep it simple for now and remove your other costs and see if your hierarchy works. You could also try making 3 different .shp files but I sure there is a concise way of doing this. Sorry if I cannot be more useful. perhaps someone else can help. – I Heart Beats Oct 1 '14 at 18:16
  • thank you very much , I will try to remove other costs and try. – Mo Ask Oct 1 '14 at 19:56
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Ok, I tried everything again. I am working in a database so I created separate feature classes and removed all costs but length ( you need to at least have one to run the network ) yet ,it is not working. So I even made the network much simpler, I can't humanly make it simpler than this. Attached are the pictures:

Note: the red line hierarchy :1

The green line :3

Two different feature class in one dataset

enter image description here enter image description here enter image description here enter image description here

  • I can give you my Highway, Major Roads and Roads .shp files if you want to play with them. If I use these to create a network they are automatically classified in the correct hierarchy. Let me know if that would help. – I Heart Beats Oct 2 '14 at 0:14
  • Where should I send them to? – I Heart Beats Oct 2 '14 at 16:37
  • I can email, the file is only 2.5 MBs. I cropped it to a small square so you will have a bunch of data to play with. – I Heart Beats Oct 2 '14 at 16:44
  • sent, let me know if you have trouble opening the data – I Heart Beats Oct 2 '14 at 18:05
  • yeah apparently , I can't open it or don't know how to open it . – Mo Ask Oct 2 '14 at 18:27
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Ok,so I think I found an answer to my problem.

Basically, hierarchy is used in long-distance networks where a lot of routes must be solved. Say if you are traveling from Vancouver to Seattle, hierarchy will help you solve the route faster. Instead of solving for all small routes, the solver will solve based on hierarchy and excludes smaller roads until it is not possible not to traverse them.

So in my example it does not matter if I define hierarchy or not. Because the network is small and hierarchy won't be considered,instead the network will solve based on cost.

The closest solution I got to my own problem for the aforesaid example is defining a restriction in network as "Avoid High" or "Avoid Medium".

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