Latest Contributions by mcKinkade

Yeah. Interesting approach but the data that I have or any decent size dataset this would not be fun to put together. Imagine doing that for 1,000 case records and 14 facilities. Also, I am looking at travel distance, not time, but I understand that this is just an example. Thanks for illustrating though. ... View more

Thanks. That still sounds like a lot more work than what I am doing. Actually, I am done. I ran the OD 14 times and transferred the distances to the cases. If there would have been more facilities, then my method would have been very painful. It was painful enough. Of course, I would have built a model to do it then but there still has to be an easier way to solve the problem. This is very clumsy. Now I have to deal with the ones that wouldn't create a route, which is a couple hundred. That is a whole other process to figure out. ... View more

Just to come back to this.  So, in my case, where I have 14 facilities and 1,000 cases. I can't see how to make this work.  I tried it by loading the stops from the cases by setting the route name as the facility and also loading the facilities as stops with the routename as the facility but it didn't work.  It appears, from your description, that I would need to do this 1,000 times and loading each individually.  Am I missing something?  ... View more

Thank you for the response.  I don't see how the Route method will work.  The New Route allows you to choose stops and routes versus incidents and facilities.  I don't see a method of choosing a "stop" from the attribute table in the cases to indicate that is the destination.  The stops could be the facilities so that aspect is correct but not the rest.  Unless I am missing something.  As of right now, I only see the method that I am using which is: - Use the OD matrix - Select all cases that went to facility A in the "Origins" layer - Select facility A in the "Destination" layer - Run the OD matrix tool    - Load the Selected Origins into the Origins Layer in the OD Cost Matrix (setting the Name field in the Location Analysis Properties section to "ID" of the Load Locations dialog so that I can tell which Origin is going to which Destination)    - Load the Selected Destination into the Destination Layer in the OD Cost Matrix (setting the Name field in the Location Analysis Properties section to "Facility" of the Load Locations dialog so that I can tell which Destination is used)  - Solve the OD Cost Analysis - This result is a Line Layer showing the Distance between the Selected Cases (Origins) and Selected Facility (Destination).  Just to be clear the geometry on the screen is the straight line but the Total Length in the attribute table is network distance. - I then export the lines into a layer stored in my geodatabase - Create an attribute field called ID in the Lines layer - Use the left function in the field calculator to extract out the ID only, since it has both the ID and facility in the same field - Join the attribute Lines table back to my Cases Table by the ID field - Use the field calculator to transfer the distance from the Lines layer into the Cases layer. - Start over with the next facility (I guess that I could make a quick model to do this but I can probably do it manually just about as fast as perfecting the model). It is 14 facilities and about 1,000 cases so I need to do this 14 times. This doesn't count the ones that, for some reason, don't create routes.  I will deal with those after getting all the ones that will map. I would be interested to hear about another method and just to recap, here is what I have and what I need: - I have a disease case (home of a person with a certain disease) layer that has the case ID and the facility where they went, amongst other variables - I have a facility layer with the facilities where they went. What I need is the network (not straight line) distance between the home of the case and the facility but this distance needs to be## back in the case layer as an attribute for analysis. ... View more

So, the OD Cost Matrix doesn't work for what I need.  I ran it again and it does create a table of cases to facilities but it creates a table of all cases to all facilities.  I don't see a way to tell it to use an attribute field to determine the destination.  Also, it didn't create routes for some at all.  It just gave a message that a route could not be determined even though they are snapped to the road network. It did give a total-length attribute in the Lines table and I assume it is the network distance.  I did a quick check by using the measuring tool and comparing the length of the some of the straight lines to the value in the Lines table and the numbers are different. The distance in the table is longer so it appears to work correctly. I guess that I could select the cases by facility in the cases layer and then the facility that they went to in the facility layer and run it.  Then it should only map those cases to their facility and then repeat for each facility.  That may work but will be tedious. Surely there is a better way to do it.  Also, there is still the challenge of getting the distance data back in the source cases layer since they assign Location names and not the ID from the cases. This seems like an oversight by the developers.  You should be able to have an ID field from both origins and destinations travel with the data to the Line layer so that you know which ones that they mapping. ... View more

Thank you.  The first time that I ran it, it went from each case to all facilities so I will need to figure out why.  My layer of cases have the facility as an attribute in the table so I need to figure out how to only give me the distance to their respective facility that they visited.  I could do what I did with the Get Closest Facility tool and select all of the cases that went to one facility and then select that facility in the facility layer but I will play with it.  I am sure this type of analysis has been done many times so I am surprised that there aren't more articles about it. ... View more

Thank you for the response.  I will look at this.  It also looks like the OD cost matrix may work.  I don't need the actual routes, just the distances between the cases and the facilities so that I can analyze those distances and the impact on mortality.  I tried the OD cost matrix before but since it drew straight lines between them, I thought that the distances were straight line distance and not network distance but I read an article today that said that it draws straight lines but stores network distance.  If it does that, then I am set. ... View more