Help with ULTRA-CSA queries

[Abdallah-Abuaisha]

Greetings! I need some guidance on how to run ULTRA-CSA queries using the provided networks (e.g., London and Switzerland). Specifically, when using the command runULTRACSAQueries in the ./ULTRA application, which files should be used as inputs?

My understanding is as follows:

1. For "CSA input file", I first converted the "intermediate.binary" file located in London/Walking/Full to "csa.binary" file using the "intermediateToCSA" command in ./Network application. I then used this file as the first argument.
2. For the "CH data", I used the CH files found in London/Walking/Contracted (i.e., London/Walking/Contracted/ch).

Is that the correct way to run ULTRA-CSA queries?

When I follow this process, I sometimes encounter errors (e.g., "segmentation fault" or "bus error"), while at other times, it seems to work but takes longer than expected, and the runtimes do not seem right (e.g., for London I get ~155ms initialisation and ~2.5ms scan!).

P.S. I am using a Mac M1 machine which does not support OpenMP. I used libomp instead and made some changes to the MultiThreading.h file to compile without errors. However, I don't think this has anything to do with running queries with the provided networks without any preprocessing. Please correct me if I am wrong.

Also, is there any relevance of the London/Original directory in this context? What does it actually represent?

Apologies for the lengthy post.

Thank you!

[jonas-sauer]

It seems that you did not run the preprocessing steps that are needed for ULTRA-CSA. The files we provide do not include the output of these steps, so you have to create them yourself like this:

1. Run intermediateToCSA with input file London/Walking/Full/intermediate.binary and output file London/Walking/Full/csa.binary.
2. Run computeStopToStopShortcuts with input file London/Walking/Contracted/raptor.binary and output file London/Walking/Shortcuts/raptor.binary.
3. The produced output is in RAPTOR format. You need to convert this to CSA format manually: Copy London/Walking/Full/csa.binary to London/Walking/Shortcuts/csa.binary. Then rename all the London/Walking/Shortcuts/raptor.binary.graph.* files to `csa.binary.graph.*.
4. Run buildCH with input file London/Walking/Full/csa.binary.graphand output fileLondon/Walking/CH/ch`.
5. Run runULTRACSAQueries with CSA input file London/Walking/Shortcuts/csa.binary and CH data London/Walking/CH/ch.

As for the London/Original directory, this is the original public transit network as retrieved from Transport for London, without the OpenStreetMap footpath graph.