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I have a road feature class layer containing parts like 1_10, 1_20. 2_10, 2_20... etc. 1_, 2_ is later used to create the route and _10, _20 is indicating the direction (the road feature classes were digitized in the same direction - they told me at least!). In this feature classe I calculate the "from" and "to" values for each segment. Ater that I create a route with arcpy.CreateRoutes_lr that seems to work great. Now for this route, linear events are collected over time.

After some time there are changes in the road feature class. So my arcpy script now recalculates the new lengths of the road segments and their "from" and "to" values, then creates a new route. This all seems to work fine BUT I am not able to transform the old events from the old route to the new route with arcpy.TransformRouteEvents_lr. I get a lot of event artifacts (like 0.5m long) and even events from lets say route 7 are "mapped" to route 10, or Event X is on route 10 and 11... However I think the most errors are like ths (the events are basing on the original segments):

  • Event1 on route1 from 0 to 20
  • Event2 on route1 from 20 to 30
  • Event3 on route1 from 0 to 25 ??!!!

Another problem is that my routes consists of loops which I think is an additional challenge.

I also tried a workaround as creating a new feature class with the old routes and the old events and then with arcpy.LocateFeaturesAlongRoutes_lr to map it on the new routes but that does not seem to work either (actually I have quite similar results as with the transform function).

I dont want to map old events on a changed/new routes (since that makes no sence for pavement). And this seems to work at least. The problems are events on routes that have not changed, but maybe the from/to values of the events must be recalculated.

I hope this wall of text makes sense somehow and unfortunately I can not post pictures yet. Any help is really appreciated!

Edit: after doing some research I found out that all features that are not a single line create errors so for example Y-or T-junctions in a route, or looping routes.

share|improve this question
Although this topic doesn't seem to catch a lot of attention I think I found the solution and would like to share. From ESRI bug site: . But the suggested workaround does not work very well in my case because only loops are adressed. To overcome problems with intersections etc. I also adjusted the M_FROM values (except the M_FROM=0). So now I have calculated: M_FROM + 1m, M_To-1m and it seems to work. However I am still searching for the smalles possible correction value (0.001 like suggested by ESRI doesn't work in my case). – simon134679 Jan 24 '13 at 11:52

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