Geographic Information Systems Stack Exchange is a question and answer site for cartographers, geographers and GIS professionals. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm new to ArcPy and ArcMap but I do have programming experience. What I am trying to accomplish is to take over 22,000 signs from a database and place them on a map in reference to a street layer that is there. The problem is that there is no lat/lng but the database specifies the road it is on, and the two intersections it is inbetween and the distance it is from the first intersection. I found an example of a trace tool and I am attempting to use that with little luck. I have a mainline layer of the road that I can trace and I have intersection points to reference but again, I am new to ArcMap and ArcPy so any help in the right direction would be great.

I am thinking that I will put in a loop to select the intersection that corresponds with the sign and then trace the distance from that intersection towards the other intersection point. The loop is not a problem but the trace function is rather foreign to me so I was hoping someone could provide me with a place to find some good examples or just a basic overview of how to implement a trace function. The ArcGIS site wasn't much help. Thanks a lot!

share|improve this question
up vote 0 down vote accepted

What you are describing is known as Linear Referencing (or Dynamic Segmentation or Chainage). You should find that much easier to use than pursuing any "trace" method. The latter is great for editing but I consider it to be inaccessible to ArcPy.

share|improve this answer
Slightly lengthy way of doing it but I am currently using CreateRoutes_lr to create a route. Then I use LocateFeaturesAlongRoutes_lr to the locate to the point that I need and placing a point by using MakeRouteEventLayer_lr. Then from there I am working on correctly offsetting the point. The trouble now is determining if I need to flip the line or not but Linear Referencing was definitely the way to go. – user2521341 Jul 31 '13 at 16:40

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.