Latest Contributions by JaySandhu

You can add an attribute value on your transfer stations that will specify the wait time or delay or penalty of taking that transfer. if this will is the same for all transfer stations then you can specify a constant value else you need to add a field to the transfer station attribute table and calculate it to the penalty values. Bring up the properties of the network dataset and for the Attribute tab, click on the evaluators and then select the impedance attribute you are using, and then either map it to the field or change the type to a constant and enter a constant penalty factor. By the way, you can see how these values were set in the sample Paris dataset, choose the PedestrianTime and look at the Transfer_Stations being set to a field value from a field called Transittim. Jay Sandhu ... View more

Generally speaking, for solving routing problems, a file geodatabase network dataset will have the best performance. You should also look into the gp tool DissolveNetwork to make a better performing network dataset. http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//00480000000w000000.htm Regards, Jay Sandhu ... View more

Do you have a network dataset to model the sea lanes, etc or just plain sea? If you do not have a network to use in this case then i suggest you look at Spatial Analyst for using a raster surface and look at the Euclidean Allocation or the Cost Allocation functions: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Euclidean_Allocation/009z0000001m000000/ Jay Sandhu ... View more

Omar, If you cannot find paths then most likely you have connectivity problems in your data. Zero length edges will not be an issue though you may want to look at a couple of them to see why you are getting that error. After you have done a build network, the log files are in your %TEMP% folder. There will be a build.txt and builderrors.txt. However connectivity issues will not show up here as that cannot be detected. I suggest you do a service area with the lines (not polygon option) from one location with a big break value and see if you can reach your entire network. If you cannot then look at the places where the service area lines stopped and zoom in to find your data problems and fix and rebuild and re-run the service area. Another quick way to find errors would be to copy the street data to a new file geodatabase/feature dataset and then build a "geometric network" and then use the Utility Network Analysis toolbar to place an edge flag somewhere and choose the Find Disconnected option and solve. Jay Sandhu ... View more

If some destinations are unlocated, zoom in to them to see why? Most likely they are further away from any road. The default maximum search tolerance is 5000 meters. You can change this on the layer properties under the locations tab. Increase it to say 20000 meters and re-locate them again (you can in the NA Window, right-click on the Destinations and choose Recalculate Location Fields and then select Unlocated) If you can't find some paths, isolate two points (an origin and destination pair) and ran a route/path through them. It will most likely not find a path. It may be disconnected parts of the network. You can then do a service area  from one of these locations and see how far you can go to try to identify the problem area. Jay Sandhu ... View more

If all paths are not found then that means some destinations are not reachable or unlocated on the network. This can either be due to connectivity issues where some edges are not connected to other or it could be due to restrictions and one way streets. If you have restrictions, try turning them off and re-solve to see if you get more or all the paths. Jay Sandhu ... View more

See the section "Properly Defined Turns" here: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//00470000000p000000.htm It may describe the sitution you have as to why some turns are not getting created. Jay Sandhu ... View more

Use the Closest Facility instead of the Route solver. Load all your destinations as Facilities and your start location as an Incident. Bring up the properties of the layer and on the Analysis tab set the number of facilities to find equal to your destinations and solve. You will get N routes. More info here: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Closest_facility_analysis/00470000004n000000/ Jay Sandhu ... View more

Hierarchy is useful for long distance routing. Say going from Paris to Berlin. If you are solving for pedestrian routes then you do not need to set up a hierarchy. All connections are fine and it runs ok, however it often does not recognise points (facilities) that are lying close to the urban path layer i.e. Path nodes/lines and Connect nodes/lines. It seems to prefer the ITN road network over the urban path network. What is this "it" that does not recognise points lying close to the urban path layer? What are you trying to achive? I can move them to a new location but because I'm using a population centred X Y location, I am reluctant to do this. Are you having trouble snapping your start/end points to the urban path layer? If yes, you can turn off the ITN layer to snap on in the Locations Tab of the Route layer properties. At the bottom are the snapping options where you can set which layers point will snap to. Jay Sandhu ... View more

If you solve a large closest facility problem in ArcMap and then write it out as an MXD it will take a lot of space. Is there a reason you need to save this in a map document? Can you export out the lines layer to a feature class (shape file or geodatabase) and then add it to the ArcMap TOC and save that map document? that way the data is not saved in the map document. You could also export the entire CF layer to disk to save a copy as well. Jay Sandhu ... View more

The first part of using a shapefile for routing is to create the connectivity graph. As I explained in my previous post, first part is to create a network dataset that goes along with the shape file and then you can use that to query the adjacencies and write your own algorithm. Here is how you can create the network dataset: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Creating_a_network_dataset/00470000000w000000/ If you have seen the network sample data and you see shapefiles for streets and junctions then there will also be another folder with a .ND extension that contains the adjaceny information in a binary format. You can take a look at the INetworkJunction object in this sample: http://help.arcgis.com/en/sdk/10.0/java_ao_adf/conceptualhelp/engine/index.html#//0001000004t0000000 Basically once you have a networkjunction then you can call its QueryEdge method to find the adjacengt edges. Some more help here: http://help.arcgis.com/en/sdk/10.0/java_ao_adf/api/arcobjects/com/esri/arcgis/geodatabase/inetworkjunction.html Jay Sandhu ... View more

A road dataset such as in shapefile format does not store any adjaceny (network topology information) with it. In fact there are no junctions. A road line feature class contains only roads. The actual road topology needs to be built from a set of rules that govern how roads connect, model bridge, tunnels, turn restrictions, etc. This is what the Network Analyst provides. It contains ways to make a network dataset from input line feature classes. The network dataset contains junctions and connectivity information and that can be queried. Network Analyst also provides the shortest path solver. So is your goal to write the shortest path solver or use an existing one? Jay Sandhu ... View more

Line barriers, polygon barriers and scaled cost point barriers were all added in ArcGIS 10.0 Jay Sandhu ... View more

This has been answered many times before in the forums. Basically search the forums for the ROUTENAME keyword. For example this post has more info on how to do it: http://forums.arcgis.com/threads/37149-Road-Distance-between-Multi-points?highlight=routename You may want to run gp tool "calculate locations" on your points once and then use these location fields to load them into the route layer in case you have to do this more than once. Jay Sandhu ... View more

You should post in the Network Analyst forum for better response to your network questions. There can be many ways to achieve what you may want to do. Depends on how many edges are changnig weights. One way to make a change without much work is to add a scaled cost line barrier. So select the edge you want to slow down, and in the NA Window, right click on the Line Barriers and load it as a barrier. You can set it to be a scaled cost barrier at load time or aferwards bring up the properties of the line barrier and change it scaled cost and set the scale parameter. This is a percentage slowdown or speedup. So a value of 1.1 will slow that edge down 10 percent and 0.9 will speed it up 10 percent. Regards, Jay Sandhu ... View more