Calculating the shortest route to travel ALL roads in a network

Hi @tslack​ You need the end-points as well as the mid-points. Use Snippers to get the end-points, then remove the duplicate points with a Matcher. Make the From-To line with a LineBuilder from the unique points. Then in the ShortestPathFinder reorder the From-To line (under Optimization).

Hey @DanAtSafe thanks for getting back to me. Im still struggling a bit as I looked into the data supplied and a lot of the froms and to's are missing/not complete. Does it make more sense to run my road network through TopologyBuilder? I notice this creates edges and nodes that are properly filled out.

I was hoping I could just plug the edges and nodes into ShortestPathFinder.

Most of the examples im seeing are for 5 or 6 specific stops when I want to cover every single road in the network, just in the most efficient way possible. This was my obviously failed attempt. I was hoping I could just treat every node as a stop? Any time I run any points through line builder its a disjointed mess because the nodes dont know the network structure (curves of the roads etc which leads me to believe I am misunderstanding a step)

Thanks again

@tslack​ The From-To has to be a vector/line. You're just inputting points. You can use the LineBuilder to string all the nodes together into an un-ordered line. But you also have to add a start and end point for the car. I agree with @danatsafe​ , I think you'll get better results if you use mid-points. If you only use endpoints you might miss a segment.

In ShortestPathFinder, use the Reorder From-To Line (Intermediate Points ONly. For optimization, I just used After Single Round of Iterations.

I've attached a small example. (FME 2021.2) Hopefully this gives you some ideas.

Hey thanks @Mark Stoakes​ this was really helpful in getting a better understanding of how this works.

Just a quick question, is there supposed to be that many results in the Unused table of ShortestPathFinder?

EDIT: never mind I think I get it. My brain was expecting turn by turn directions

@tslack​ I've done a little more investigation and I don't think the example I gave you will give you the results you want. Let us do a little more testing here and we'll see if ShortestPathFinder can give you what you need.

Thanks @Mark Stoakes​ I'll continue to play around with it while waiting for your response.

@tslack​ I don't think it's possible with the current algorithms we're using in the ShortestPathFinder. At the moment you can't use both:

• "Allow U-Turns" AND
• Re-order From-To Line : Intermediate Points only

I've attached my revised workspace (FME 2022.1) that fixes some errors in the early version, but it doesn't return a path because it can't get to all the line mid-points without U-turns

You might find a solution in "R" using RCaller. I'd open a new community thread if you want to pursue that. Sorry about that.

Thanks @Mark Stoakes​ really appreciate the help here