Avoid certain street types

622
5
06-15-2011 05:01 AM
MartinaRagettli
New Contributor
Hi

I would like to avoid highways or main roads when doing "best route analysis" (impedance: shortest route). What is the best and easiest way to implement this restriction?

Thanks
Tags (2)
0 Kudos
5 Replies
JoeBorgione
MVP Emeritus
Hi

I would like to avoid highways or main roads when doing "best route analysis" (impedance: shortest route). What is the best and easiest way to implement this restriction?

Thanks


The best and easiest way is what works for you.  A couple of suggestions:

Create a network feature dataset WITHOUT your highways and main roads

Place barriers on each  (yuck)

Place impedance values on them like low speed limits (if you are minimizing travel time)

Hope this helps-
That should just about do it....
0 Kudos
MartinaRagettli
New Contributor
Thank you for your suggestions.
It would be also nice to add a restriction attribute for the highways and add a parameter on the restriction. Something like that: with a car, the highways are transferable, by foot not. The mode would be the parameter. However, I'm not sure if this is possible to do. So far, I did not manage to implement this. The option "parameters" in the Network Dataset properties was always inactive (???).
What do you think?
0 Kudos
MartinaRagettli
New Contributor
To your suggestion "Place impedance values on them like low speed limits". How would you do that? By creating a new cost attribute? How would you then set the evaluators?

Thank you so much
0 Kudos
JoeBorgione
MVP Emeritus
To your suggestion "Place impedance values on them like low speed limits". How would you do that? By creating a new cost attribute? How would you then set the evaluators?

Thank you so much


I'm sorry, I don't have the time and this forum dosen't have the space for a complete description of Network Analysis.  Assuming you are using ArcGIS 10.x may I suggest you start here, and if you are using 9.3, take a look here.

There are a couple of tutorials out there too: just google network analyst tutorial and you'll find them.

Typically, the street centerline data I use in the network have various attributes that I can use in NA.  For example SpeedLimit.  With it you can do a calculation with the segment length to derive a 'cost' of travel time needed to traverse any given street segment.  In my case, I keep freeways at 65 mph; it sounds like you may want to knock them down to 1 mph, thus making traversing the freeway segments unattractive to the solver if travel time is to be minimized.
That should just about do it....
0 Kudos
AlexeyTereshenkov
Regular Contributor III
Joe, good point.

I agree with Joe, the best way for you to get started is to become familiar with the concepts first. I bet you will find all your questions answered in the Help, it is very comprehensive.

ArcGIS Network Tutorial is available online at:
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Exercise_1_Creating_a_network_dataset/...

Or as .pdf file:
http://help.arcgis.com/en/arcgisdesktop/10.0/pdf/network-analyst-tutorial.pdf

Good luck.
0 Kudos