Trace Function Barrier on shape length not working

Question

Hi everyone,

I'm going crazy over a trace I'm trying to do.

I'm trying to stop a trace when the sum of the length of the lines reaches 20 meters. I read that the correct way to reach this goal is to use the Function Barriers or Filter Function Barriers.

The problem is that it seems like the trace stops working correctly when it reaches a certain treshold

Trace Downstream with a Filter Function Barrier of 10 meters = CORRECT RESULT

Same Trace Downstream with a Filter Function Barrier of 20 meters = INCORRECT RESULT

Why is the line longer than 20 m and "shifted" from the starting point?

I tried doing this in a FGDB enviroment both on a custom UN and the Water Foundation with the same results.

Am I doing something wrong?

Thank you in advance for any help.

Lorenzo

YulissaCamacho · Answer

YulissaCamacho · Answer

Hi,

I'm not very sure that this is the same case. But we tried to do the same thing, here is what help us to get a much correct result:

Networks often have paths that fork into multiple paths. You may at times want to consider all forked paths together (global), and at other times as separate from one another (local). Consider an example in which you want to trace a set distance along a pipe network. In this scenario, if the starting point is placed at a fork with three paths, and the trace is set to trace 3 miles down the pipes using global values, the trace will travel 1 mile down each of the three forked paths. By enabling the Use Local Values option, the trace will travel 3 miles down each of the three forked paths. It is important to note that only one starting point is allowed when running a trace using a function barrier with the Use Local Values option.

More than one barrier type can be used at once. Combining barriers allows you to control a group of diverse, precise types of barriers. For example, you want to run a trace and have it stop at any open device, but you don't want the trace to travel more than 500 meters beyond the starting point. To accomplish this, you can use a barrier condition to control the type of open device that stops a trace, and you can use a function barrier to calculate the length of the line you travel and set a limit of 500.

Function barriers support apportionable situations and return a portion of the function value calculated for a line that has a barrier located midspan.

For example, in a pipe network, you want a trace to stop when it reaches 500 meters. The 500th meter may not be at the end of a pipe; it may be midspan along a pipe. In this case, the trace stops midspan, but the entire pipe is considered a barrier. The features returned in the results of the trace will add up to less than 500 meters.

https://pro.arcgis.com/en/pro-app/latest/help/data/utility-network/barriers.htm

lzorloni · Answer

Thank you Robert for your quick answer! At least now I know it's a bug

Lorenzo