topic Re: Calulating number of turns along a route in ArcGIS Network Analyst Questions

Calulating number of turns along a route

KateSchaefer — Wed, 25 Apr 2012 22:00:36 GMT

Hello,

I'm am using NA's Closest Facility solver to calculate routes between incidents and the closest fire station. The processes works fine and I have about 385 different routes. Is it possible to calculate or find out the number of turns along each route? And better yet, whether it was a left or right turn? Any help would be greatly appreciated.

Thanks!

Re: Calulating number of turns along a route

JaySandhu — Thu, 26 Apr 2012 16:56:28 GMT

Are you looking at counting turns that may be part of a turn feature class? In that case if their are turn restrictions they will be avoided. Only turns that have delays assoicated with them may be traversed. In that case use the traversal addin to generate the feature classes, including turns, after your paths are solved.
http://resources.arcgis.com/gallery/file/ArcObjects-.NET-API-Code-Gallery/details?entryID=C8A2186E-1422-2418-3494-48812C8DB8DE

But if you are looking at simply "bends" along your paths, then you have to look at the geometry at each intersection to see if a "turn" is being made. One simple way to get this information reported is to get the directions of a route. It will report left and right turns. You can save the directions as text or XML. With XML you may be able to parse out what you need, but this may not be in the best way to summerize.

Can the network dataset you are using to solve editable to add more attributes for later use? That may give more options on reporting turn information.

Jay Sandhu

Re: Calulating number of turns along a route

KateSchaefer — Thu, 26 Apr 2012 19:28:25 GMT

Hi Jay,

Thanks so much! I installed and ran the Traversal Result tool and it gave me exactly what I needed. For others in the same boat, it creates (among other things) a "TRFC_Turns" feature class. This counted each intersection that the route took and gave me times for each intersection. Based on the times I was able to classify if the route went straight through the intersection or if it took a left or right.

Thanks again, this worked great!

Kate

Re: Calulating number of turns along a route

NagendraDhakar — Sat, 19 May 2012 22:16:32 GMT

Hi,
I am also trying to find no. of turns (left and right) along a route. But I have ArcGIS 9.3, and I guess, this add-in is for ArcGIS 10 as it doesn't recognize 9.3. So, it would be helpful for me if any one can please post the VBA code associated with the add-in?
Also, I know that turns can be accessed via traversal but when I use that with my network data set it gives me a blank shapefile, however, junctions and edges outputs are perfectly fine. That left me wondering if it has anything to do with the way I set up my turns while creating the network dataset. That time, I checked "Yes" to the question "Do you want to model turns in this network?" with "Global turns" checked as the turn sources. Also, at the end, I established driving directions by just providing "Street Name Fields". Alternatively, I tried using INAStreetDirectionsAgent, but it gives me the directions in XML output. I couldn't find any other useful output from that. Even, with the XML output I don't know how to use it to get the number of turns.

Any help is appreciated.

Thanks,
Nagendra

Re: Calulating number of turns along a route

JaySandhu — Mon, 21 May 2012 14:54:45 GMT

The VAB is posted below. It will work for turns if they exist in your data.
Jay Sandhu

Public Sub AddNATraversalResultToArcMap()
Dim pMxDoc As IMxDocument
Dim pNetworkAnalystExtension As INetworkAnalystExtension
Dim pNALayer As INALayer
Dim pFLayer As IFeatureLayer
Dim pTraversalResultQuery As INATraversalResultQuery
Dim pNATraversalResultEdit As INATraversalResultEdit

Set pMxDoc = ThisDocument
Set pNetworkAnalystExtension = Application.FindExtensionByName("Network Analyst")
Set pNALayer = pNetworkAnalystExtension.NAWindow.ActiveAnalysis
Set pTraversalResultQuery = pNALayer.Context.Result
Set pNATraversalResultEdit = pTraversalResultQuery

'Infer Geometry
pNATraversalResultEdit.InferGeometry "", Nothing, New CancelTracker

'Get the Edges and add as a layer
Set pFLayer = New FeatureLayer
Set pFLayer.FeatureClass = pTraversalResultQuery.FeatureClass(esriNETEdge)
pFLayer.Name = pFLayer.FeatureClass.AliasName
pMxDoc.FocusMap.AddLayer pFLayer

'Get the Junctions and add as a layer
Set pFLayer = New FeatureLayer
Set pFLayer.FeatureClass = pTraversalResultQuery.FeatureClass(esriNETJunction)
pFLayer.Name = pFLayer.FeatureClass.AliasName
pMxDoc.FocusMap.AddLayer pFLayer

'Get the Turns and add as a layer
Set pFLayer = New FeatureLayer
Set pFLayer.FeatureClass = pTraversalResultQuery.FeatureClass(esriNETTurn)
pFLayer.Name = pFLayer.FeatureClass.AliasName
pMxDoc.FocusMap.AddLayer pFLayer

End Sub

Re: Calulating number of turns along a route

NagendraDhakar — Mon, 21 May 2012 15:03:22 GMT

Hi Jay,
Thank you for the reply. I used the same VBA code for turns but output had nothing. Btw, if street directions are available doesn't it mean that turns are there too? if not then do we have to import turns separately?

Thanks,

Nagendra

Re: Calulating number of turns along a route

JaySandhu — Mon, 21 May 2012 15:11:51 GMT

The street directions looks at every edge of a route as it connects to the next edge, computes the angle and then decides what angle exists before it can say left or right turn. As I mentioned, this VBA (or the new AddIn) export out the turn features that were part of the network dataset. it cannot export what does not exist. You will have to post process the Edges that are exported out of here to determine left/right turns.

Jay Sandhu

Re: Calulating number of turns along a route

NagendraDhakar — Mon, 21 May 2012 15:24:46 GMT

Hi Jay,
Then is there any way to get these turns through street direction? I can export the directions as a XML output but how can I get left and right turns from that? If i try to calculate angles between edges than it will increase the computing time. So, I am thinking if there is something in the results that can be used for this.

Thanks,

Nagendra

Re: Calulating number of turns along a route

JaySandhu — Mon, 21 May 2012 15:34:24 GMT

What are your goals? Is it know the number of turns (define turn!)?
That is, is it to know left/right turns only when street name changes? Or is it to know bends or turns in the road even when the street name does not change?

At a minimum, you could export the directions and count how many "left" and "right" words are contained in it!
Jay Sandhu

Re: Calulating number of turns along a route

NagendraDhakar — Mon, 21 May 2012 16:28:10 GMT

Hi Jay,
My goal is to count number of left and right turns in a route and turns should be made at an intersections. If nothing works out, I was thinking to read the XML file to get count of "left" and "right" words. Btw, how does ArcGIS decide left and right turns?

Thanks,
Nagendra

Re: Calulating number of turns along a route

NagendraDhakar — Sat, 11 Dec 2021 15:14:58 GMT

Also, do you know how to read A XML file, i am having difficulty in doing that. I am using following for this:

Dim xmlStream As esriSystem.IXMLStream
Dim xmlReader As esriSystem.IXMLReader

Set xmlStream = New esriSystem.xmlStream
xmlStream.LoadFromFile "D:\Directions.xml"

Set xmlReader = New esriSystem.xmlReader
xmlReader.ReadFrom xmlStream

I don't know what to do after this. However, I tried several methods of IXMLReader but couldn't get anything working.

Thanks,
Nagendra

Re: Calulating number of turns along a route

jyakypetter — Wed, 30 May 2012 03:05:59 GMT

Hi,
I am also annoying to find no. of turns (left and right) the length of a route. But I have ArcGIS 9.3, and I guess, this add-in is for ArcGIS 10 as it doesn't identify 9.3. So, it would be accommodating for me if anyone can please post the VBA code linked with the add-in?
Also, I know that turns can be access via traversal but when I use that with my network data set it gives me a blank shapefile, however, junctions and limits output are completely fine. That left me wondering if it has anything to do with the way I set up my turns while create the network dataset. That time, I checked "Yes" to the question "Do you want to model turns in this network?" with "Global turns" checkered as the turn source. Also, at the end, I recognized driving instructions by just as long as "Street Name Fields". Alternatively, I tried using INAStreetDirectionsAgent, but it gives me the directions in XML output. I couldn't find any other useful output from that. Even, with the XML output I don't know how to use it to get the number of turns�?��?��?��?��?��?��?��?��?��?��?��?��?��?��?�..
liposuction Miami

Re: Calulating number of turns along a route

JaySandhu — Wed, 30 May 2012 14:15:27 GMT

The VBA code is already linked into this forum post.
Jay Sandhu

Re: Calulating number of turns along a route

liemnguyen — Thu, 10 Jan 2019 02:17:05 GMT

Dear Jay,

Could you please share me the other link to download Traversal addin?

The current link has been broken.

Thank you so much!

Re: Calulating number of turns along a route

JaySandhu — Thu, 10 Jan 2019 17:08:55 GMT

You can use the GP tool to get to the traversal results.

Copy Traversed Source Features—Help | ArcGIS Desktop