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Hi Joseph, It seems like there's 2 main questions here, so I'll write them out below with answers. 1) How does network analysis deal with inputs which are not directly located on a network edge/junction? When loading inputs into a network analysis layer, network analysis objects are created for each input. The network analysis object has it's own network location, which is it's position on the network. If the object isn't directly on a network feature, then the analysis layer will do a search to find the closest network feature and kind of snap to the feature. The proportional location of the point on the line becomes the network location. Check out What are network analysis objects?—Help | ArcGIS Desktop for more information on network analysis objects and network locations. 2) Is the Location-Allocation analysis using Dijkstra's algorithm? The LA solver uses an OD Cost Matrix as part of it's calculation, and the OD Cost Matrix uses an algorithm which is based on Dijkstra's. You can read more about the algorithms used in network analysis here Algorithms used by the ArcGIS Network Analyst extension—ArcGIS Pro | ArcGIS Desktop I hope this answers your questions! -Rachel
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11-08-2019
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Hi Bill, You don't need to be the admin. For the account, there should be someone (or multiple someones) who is designated as the contact for Esri Technical Support. That person(s) can either start a chat, call Esri Technical Support (1-888-377-4575), or create a case online from their MyEsri account. If you are the contact for Esri Technical Support, you should be able to tell by logging in to your MyEsri account. If you are the contact, you should see something like a Support section and in there you'll see a button for logging a case. Alternately, as long as you know your customer number, you can call in to Support and try to create a case. If you aren't the contact, the receptionist who helps you can tell you who is. And even if you aren't the Support contact, you can still get a case. The person who is the contact will get the case but they can have you as the secondary contact on it and specify that all communication be with you. So there are plenty of options. If you still have trouble with getting a case, please let me know and I'll see what I can find for you. Regards, Rachel
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11-08-2019
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Hi Vikas, I'm glad that removing the incidents and facilities as sources of your network dataset helped. So are you still getting the error that no facilities were found for your incidents? As to what you are trying to do, if I'm understanding it correctly, if you like the output routes that the CF solver generates, you could run the "Copy Traversed Source Features" tool to get all the individual road segments, then do a spatial join with them back to the original street segments, so that you get streets with all the attributes of the generated routes and of the original streets. Does that sound like what you want? -Rachel
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11-07-2018
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Hi Vikas, First thing that comes to mind is that the points that you mean to use as facilities and incidents should not be included as sources in the network dataset. Likely this is not causing the solve to not find anything, but without seeing your data, I can't say for certain. And also, it's just best practice to not include point that are meant to be inputs into the analysis as sources in the network dataset. Second, I think we need to know more about your analysis settings and the network dataset itself. The error "No 'Facilities' found for 'Location X' on 'Incidents'" could indicate several things. - If you've set an impedance cutoff, then perhaps there are no facilities close enough to the incidents to be reached inside that cutoff. If you think that the incidents should be close enough to facilities, then perhaps the impedance is looking at the wrong field or the numbers in that field are not correct. - There could be a lot of connectivity problems in the network dataset, so that once the route leaves the incidents, it gets stuck on a street and can't move off of it. These problems could be caused by gaps or connecting at midpoints or other things. You'll want to check your connectivity policy on the network dataset and make sure it is the right one. Setting up a topology on your streets and employing rules like Must Not Overlap, Must Not Self Overlap, Must Not Self Intersect, Must Not Intersect or Touch Interior (just as examples, you can choose which ever rules are most appropriate for your data). Though if you use elevation values, you'll also need to check to make sure that the z values or elevation field values at intersections match. While you may not use Any Vertex connectivity, I like the article Problem: Connectivity isn't established properly when using an Any Vertex connectivity policy and elevation fields explains how elevation works. A tool I find very helpful for troubleshooting connectivity issues is the Network Identify tool, which right now is only in ArcMap, not Pro (though it is planned to get the tool into Pro). So you'd have to switch to ArcMap to use that. So I'd start there, with checking your analysis settings and doing a QA on your network dataset to make sure the connectivity of the streets is correct. I hope this helps! -Rachel
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11-07-2018
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Have you ever tried to get a route between several points in ArcMap and received the message "Warning: Location X in 'Stops' is on a non-traversable network element position"? You do a little research and find out you need to enable the setting "Exclude restricted portions of the network". Even after turning that setting on, you still get the error. What's going on? If you try the same route in ArcGIS Pro, there’s no error message. And you can't find the “Exclude restricted portions of the network” setting anyway. What's going on? What is the problem here? And what is the difference between ArcMap and ArcGIS Pro? The problem that's preventing the stop from being on the route is with the network location. What is the network location? Per Esri Help documentation, “a network location is a type of network analysis object that is tied to the network; furthermore, its position on the network is input for the analysis." (Network Locations, http://bit.ly/2gfVM6m). In plain terms, it's where ArcGIS Network Analyst routes to. When ArcGIS Network Analyst solves a route, Network Analyst doesn't route to the XY location of the point. Instead, the extension will snap the point to the nearest street and calculate some location values on that street. That location is the network location. The network location can be seen in four fields*: SourceID, SourceOID, PosAlong, and SideofEdge. SourceID: This will be the name of the source feature class that the network location is on. SourceOID: The OID of the source feature that the network location is on in the source feature class. PosAlong: The position along the digitized direction of the source line feature**. The number is expressed as a ratio, between 0 and 1. For example, a PosAlong value of 0.557 indicates that the location is 55.7% down the line. SideOfEdge: The side of the line that the original XY location is on with reference to the digitized direction of the line. The message "Warning: Location X in 'Stops' is on a non-traversable network element position" indicates that the network location for that point is on a street that is considered prohibited or non-traversable. Some examples of a location that is on a prohibited street include, but are not limited to: The analysis has been set so that it simulates driving a car, and the network location is on a pedestrian-only street. The stop is on the right side of a one-way street which is prohibited in the "along" direction***. The network location is on an unpaved road, and unpaved roads are prohibited in the analysis. You can use the Network Identify tool on an edge in the network dataset to see which network attribute restrictions (like one-way or unpaved roads) would cause the edge to be traversable or prohibited. So, the network location is on a prohibited network edge. What do you do about that? Let's continue by looking at the "Exclude restricted portions of the network" setting, since that's the setting we use to fix the error. The "Exclude restricted portions of the network" setting causes network analysis objects to locate only on elements that don't have active prohibit-restrictions, which are restrictions that are checked in the Analysis Settings tab. With this on, then a network location will not be placed on any edge considered prohibited at the time. How does it work? If the "Exclude restricted portion of the network" setting is on when ArcGIS Network Analyst is calculating the network locations, ArcGIS Network Analyst will skip any street considered prohibited and find the closest street which is traversable. Let's go back to the example of the analysis being set up to simulate driving a car, and the point is closest to a street marked as pedestrian-only. Getting more specific, let's say I work for a pizza delivery service. A customer called and ordered a pizza. They live in a college dorm, which is located on a pedestrian walkway. If I have the "Exclude restricted portions of the network" setting enabled when I load the point for that location, I'll get a route. And I'll see that it's not taking me to that pedestrian walkway; it's taking me to a point on the main road through the campus. From there, I'll park on the side of the road, get out and walk to the dorm to deliver the pizza. Then go back to my car and continue the route. This setting is where we see one of the biggest differences in network locations between ArcMap and ArcGIS Pro. Let's start with ArcMap. ArcMap In ArcMap, all network location settings are accessed through the Network Locations tab of the network analysis Layer Properties****. The order of changing settings related to network location matters because network location settings in ArcMap are not retroactive—they don’t go back and change any network locations already calculated. So, if you change a network location setting after loading your locations, you'll need to recalculate the network locations. By default, ArcGIS Network Analyst in ArcMap does not use the "Exclude restricted portions of the network” setting, so you will need to turn it on. Either turn it on before loading the locations or after—if after, be sure to recalculate the network locations before solving. In the situation described in the beginning of this blog, the "Exclude restricted portions of the network" was turned on, but the network locations were not recalculated. Here are some example steps to follow to ensure stops are included in the route: Load the locations into the analysis layer. Turn on "Exclude restricted portions of the network". Make any remaining changes to the analysis settings, including which restrictions are turned on or off. Recalculate the network locations *****. Solve ArcGIS Pro ArcGIS Pro has more advanced network location settings. All settings are found in the Add Locations geoprocessing tool, which loads the points into the network analysis layer and calculates the network locations. So, it makes sense that the network location settings are found in the Add Locations geoprocessing tool. But wait, where is the "Exclude restricted portions of the network"? It's not gone; it's still there. In fact, ArcGIS Pro turns it on by default, so it's always in effect. Also, ArcGIS Pro automatically recalculates network locations for locations affected by setting changes automatically before the solve. So, you do not need to manually recalculate locations in ArcGIS Pro; it does it for you. These are some of the most used settings to keep in mind when working with ArcGIS Network Analyst, but there are many more. I encourage you to check out the settings and see how they can improve your network analysis. Resources: “What are network analysis objects?”: http://bit.ly/2CL5yep “The Network Identify tool”: http://bit.ly/1Mpn5lC “Snapping network locations with Build Query”: http://bit.ly/2uNiBay “Opening the network analysis Layer Properties dialog box”: http://bit.ly/2xmzMwJ “Recalculating location fields”: http://bit.ly/2EcJO7c * For points. Network locations for lines and polygons (for barriers, route zones, etc.) are stored in a single blob field and cannot be easily read. ** One of the easiest ways to see the digitized direction of a line is to add an arrow at the end of the line symbology. In ArcMap and ArcGIS Pro, there is a default symbology called “Arrow at End” that can be used. *** “Along” indicates travelling with the digitized direction. “Against” indicates travelling against the digitized direction. **** Common ways to access the network analysis Layer Properties are either double-clicking the analysis layer name in the Table of Contents or by clicking the Layer Properties box in the top-right corner of the Network Analysis window. ***** To recalculate the network locations, right-click the sublayer in the Network Analysis window, and choose Recalculate Location Fields.
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10-17-2018
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Hi Ana, Generate Events doesn't update the measures. It takes whatever measures are in the attribute table for that event and recreates the geometry, the shape, from the route based on those measures. From the documentation Generate Events—Location Referencing for Roads and Highways | ArcGIS Desktop , it "Re-creates shapes for event features registered with an LRS Network". So check what the measures are in the attribute table. I'm guessing they're null, if you're getting no geometry. Make sure the measures there are good then try running the tool again. -Rachel
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10-04-2018
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Hi Paul, So, I'm going to make some assumptions here and you can tell me if I'm wrong. 1) I'm assuming that your Portal is federated with your server 2) I'm assuming that you have the Network Analyst license for Server and Portal You can publish the routing service in 2 main ways, either as a Network Analysis service or as a geoprocessing service that uses Network Analyst. Route, Closest Facility and Service Area analyses can be published as NA services. All of the analyses can be published as geoprocessing services that use NA. Network analysis services—Documentation | ArcGIS Enterprise See this link for how to publish NA services Tutorial: Publish a network analysis service—Documentation | ArcGIS Enterprise Check this link for how to publish a geoprocessign service A quick tour of publishing a geoprocessing service—Documentation | ArcGIS Enterprise If going the geoprocessing service route, you can use the tools in the Network Analyst toolbox->Server toolset to create the models. Once you have the services published, you'll need to register them with the Portal as utility service. See this link for how to do that Configure utility services—Portal for ArcGIS (10.6) | ArcGIS Enterprise I hope this helps! Regards, Rachel
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09-25-2018
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Hi sotokan80 ., You could find some way to identify locations where the elevation needs to change. Like, if a bridge is intersecting a road and there is no connectivity, then there should be 2 junctions there, 1 with the elevation of the bridge and 1 with the elevation of the road. Using python, you could select all roads that intersect those locations where there are 2 system junctions. Then read through the geometry of the roads and use the firstPoint and lastPoint properties to get the coordinates of the beginning and end points. Then compare those coordinates to the coordinates of the overlapping junctions. Grab the elevation value from on of those vertices and insert it into the appropriate from or to elevation field, depending on which coordinates of the line match up with the coordinates of the vertices. That's just a very rough outline and you'll need to do some tweaking, but that could be a place to start. Regards, Rachel
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09-20-2018
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You'll need to geocode the address to get the location in a feature layer/table (which can be in memory) then pass that feature layer/table into Add Locations (Add Locations—Help | ArcGIS Desktop ). Of course for the geocoding, you'll need a geocoder or a geocoding service. If you have your own, you can use that, or you could also use Google or several other options. See the options in Geocode only one address in arcpy. or Geocode Addresses—Help | ArcGIS Desktop or arcgis desktop - How to geocode a single address in Python Script/ ModelBuilder? - Geographic Information Systems Stack … for ideas.
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06-15-2018
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Hi Luiz, The Closest Facility and OD Cost Matrix are very similar solvers that often do very similar things, but there are some nuances to each which make them better for certain situations. The Origin Destination Cost Matrix (ODCM) only solves in one direction, from the origins to the destinations. The Closest Facility (CF) solver can solve from facility to incident or from incident to facility. CF can return output shapes as the true shape of the route, with or without measure values, straight lines or no output shape at all and it can also return directions for each route. The ODCM can only return either straight lines or no shape at all and it will not return any directions. Because the ODCM does not return complicated geometry or directions, it finishes more quickly than the CF and is meant as a faster alternative to CF when dealing with large solves. There are some other differences, both on the front end and back end, but those are the main ones. If you're interested in learning more about the algorithms for each analysis, check out Algorithms used by the ArcGIS Network Analyst extension—Help | ArcGIS Desktop . Hope that helps! -Rachel
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06-15-2018
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Adding on to Kory's note, here is a great series of tutorials on how to prepare your data for a network dataset: How To: Prepare data for use with the Network Analyst extension There are several chapters in it and it covers everything from fixing basic geometry issues to setting up attributes for restrictions to modifying the global turn delay evaluator to customize your network dataset. I hope it helps! -Rachel
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01-19-2018
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Hi Ana, What kind of maintenance procedures are you doing? General database maintenance (like recreating indices) or some specific Roads and Highways procedures (like deciding conflicts during a reconcile)? Also, is your data in a file or enterprise geodatabase? -Rachel
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11-09-2017
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Hi Mathew, I was encountering the same issue so I emailed Deelesh. He has found that this error typically comes from using background processing to run the tool. In my own tests, I found that even if you are using foreground processing, if you have the 64bit background processing extension for ArcMap installed, it will still fail. I was able to get the tool to work by uninstalling the 64bit background processing and running the tool in the foreground. I think that the issue is caused by the old version of pulp installed with the tool. Newer versiond of the module do support both 32 and 64bit processing, so if you update the pulp module that comes with the tool, the issue with the background processing should go away (though I have not tried that yet.). Hope this helps! -Rachel
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11-09-2017
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So that error message does not indicate to me that it is not recognizing the NA layer as an NA layer. My thought is that there is a parameter in the NA layer that is not the correct type. I would print out the properties of the ODCM layer (ODCostMatrixSolverProperties—Help | ArcGIS Desktop ) and check each parameter, see what type of object it is and that it matches what it should be. Also check the origins and destinations and make sure they all look good. If you make a new NA layer with the exact same properties and use that in your script, do you still get the error? And can you solve the analysis in ArcMap using that same NA layer that is giving you problems now? If you have support, you can also create a support ticket for this, so you can get more directed help (Though you'd probably get many of these same questions from the support analyst who takes the case).
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09-14-2017
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Update: I just took the MakeODCostMatrixLayer example 3 (workflow) from Make OD Cost Matrix Layer—Help | ArcGIS Desktop , pasted it into a new py file, changed the data path, and it worked fine. So I'd really want to see your script and what else is going on in it.
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09-14-2017
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