topic Re: how to set up various service areas for different facilities in ArcGIS Network Analyst Questions

how to set up various service areas for different facilities

SuyunMa — Tue, 18 Dec 2012 00:37:47 GMT

Hi
I have a table that contains a list of facilities, and each facility is associated with a specific driving distance. And I want to create various service areas for all facilities, say a 10-mile service area for Facility A and 12-mile service area for Facility B. However, I couldn't figure out how to do that and really need help. Thanks a lot.

Best regards,
Suyun

Re: how to set up various service areas for different facilities

NicoleHanson — Tue, 18 Dec 2012 14:13:07 GMT

It sounds like you'll need to use the select tool, to load the specific facilities. Then use the properties to set the mile impeadance. You'll have a bunch of service areas, but it'll do what you want.

Re: how to set up various service areas for different facilities

MelindaMorang — Tue, 18 Dec 2012 14:35:02 GMT

There's a much easier way to do it than that.

When you Load Locations, you can specify a different break value for each service area using field mapping. You need a column in your input data that has the break values you want (so, 10 for Facility A, 12 for Facility B, etc.). In the field mapping table in the Load Locations dialog box, there will be an entry on the left that says "Breaks_[Impedance Attribute]", where the [ImpedanceAttribute] part is filled in with whatever impedance attributes are available in your network dataset. Click in the space next to the one you want ("Breaks_Miles" or some such), and you'll get a drop-down of the fields in your input data. Select the field in your data that has the break values (10 for Facility A, 12 for Facility B, etc.). When the Facilities sublayer is created, you'll notice that the Breaks_Miles column is now filled in with the values from the field in your input data. When you solve the service area calculation on that impedance attribute, the values in this column will override the default cutoff you give it in the settings.

Good luck!

Re: how to set up various service areas for different facilities

SuyunMa — Tue, 18 Dec 2012 16:55:25 GMT

Thank you very much for your help. I will try and let you know how it works.

Suyun

Re: how to set up various service areas for different facilities

SuyunMa — Tue, 18 Dec 2012 18:04:49 GMT

There's a much easier way to do it than that.

When you Load Locations, you can specify a different break value for each service area using field mapping. You need a column in your input data that has the break values you want (so, 10 for Facility A, 12 for Facility B, etc.). In the field mapping table in the Load Locations dialog box, there will be an entry on the left that says "Breaks_[Impedance Attribute]", where the [ImpedanceAttribute] part is filled in with whatever impedance attributes are available in your network dataset. Click in the space next to the one you want ("Breaks_Miles" or some such), and you'll get a drop-down of the fields in your input data. Select the field in your data that has the break values (10 for Facility A, 12 for Facility B, etc.). When the Facilities sublayer is created, you'll notice that the Breaks_Miles column is now filled in with the values from the field in your input data. When you solve the service area calculation on that impedance attribute, the values in this column will override the default cutoff you give it in the settings.

Good luck!

I have successfully created a facilities sublayer with right Breaks_Length for each facility. However, I still don't know how to solve the service area based on that. When I set up the Default Breaks at the Analysis Settings Tab, I could only input fix value(s) rather than a variable name.

Re: how to set up various service areas for different facilities

PatrickStevens — Wed, 19 Dec 2012 20:17:39 GMT

The fixed value you set on the service area layer properties will only be used for facilities where you did not specify an override for the break value.

For each facility where there is a Breaks_<AttributeName> for the cost you are solving against, the value in Breaks_<AttributeName> will be used for that facility. If will override the solver setting.

For example, if you have the following solver settings:

Cost attribute = TravelTime (minutes)
Breaks = 2 3 4

And the following data values

   Name       Breaks_TravelTime
---------    ---------------------
Facility1       <Null>
Facility2      20

When you solve the service area, Facility1 will generate polygons at 2, 3, and 4 minutes. Facility2 will generate a polygon at 20 minutes.

Re: how to set up various service areas for different facilities

Anonymous User — Wed, 19 Aug 2015 23:29:06 GMT

Hi Melinda,

The "Breaks_[Impedance Attribute]" option doesn't come up when I'm loading locations into the Facilties. Do you know how to ensure that option is available?

Thanks,

Brendan

Re: how to set up various service areas for different facilities

MelindaMorang — Thu, 20 Aug 2015 17:53:19 GMT

It's in the field mapping part (labeled as Location Analysis Properties below). Did you scroll all the way to the bottom of this window?