topic Re: Setting a restriction on a network in ArcGIS Network Analyst Questions

Setting a restriction on a network

GavinRudge — Sun, 18 Nov 2012 18:35:20 GMT

I have a road link with a field called DescTerm which contains a string descriptor of the type of road. I want to create a restriction which excludes the use of motorways in my nearest facility and service area calculations.
Using catalog I went into the properties of the network dataset, in the attributes tab created a new restriction. In the evaluators I used the following syntax:

restricted = False
If [DescTerm]="Motorway" Then
restricted = True
End If

I entered restricted in the value box.

I rebuilt the data set, brought it into a new map and set up a couple of points to create a route. The name of the restriction appeared already ticked in the restrictions portion of the analysis settings window of the network properties, so assumed everything was working OK, but my routes will not avoid the motorways. Can anyone tell me where I went wrong. Also when I use identify to select a section of a restricted road I see that the along property is traversable and only the against is restricted. I set the same evaluator for the from/to road links as the to/from.

Any suggestions for how to get this restriction working properly?

Many thanks,

Gavin.

Re: Setting a restriction on a network

RamB — Mon, 19 Nov 2012 01:52:08 GMT

Hi,Which version of arcgis are you using? Please refer this for 10.1

http://resources.arcgis.com/en/help/main/10.1/index.html#//0047000001s5000000

Regards,

Re: Setting a restriction on a network

GavinRudge — Mon, 19 Nov 2012 09:11:59 GMT

Hi thanks for this,

Yes I'm using ArcGIS 10 on a Windows 7 paltform. I'd seen this tutorial, and kind of followed it. I'm trying to do something much simpler, I'm really building a pedestrian network and simply want to exlude roads that pedestrians have not access to. I finally got a workaround using hierarchy. All my hierarchy =1 roads happened to be ones that pedestrians could not use, and I managed to set up an exlusion for these using a function in the evaluator based on this that excluded them and this seems to work on route solvers now - I'm still not clear about how my original approach did not work though. I now have a different and more serious problem with my network - I'll post a separate shout out for help on this, as I think this is about connectivity rather than restrictions.