September release of or-tools

I just released or-tools version 6.4.

The biggest change is that I reverted the ortools-<linux distro> specific pypi modules as we now have manylinux distro agnostic wheel files.

Here is the full change log:

Change in platforms

  • Pypi modules on Linux platforms are now delivered as wheel files using the manylinux1 tag. Thanks to Federico Ficarelli. With this change, we have backtracked the per-linux modules introduced in the July 2017 release.

New features

  • Improved scaling method used inside GLOP.
  • Fix wrapping of evaluators in the C# routing library. Thanks to DevNamedZed.
  • Improve the performance of the flatzinc presolve for large models.
  • Use the SAT backed for flatzinc by default.
  • Improve performance of the Core based approach for the sat solver.
  • Fix bug in the linear assignment algorithm that was failing incorrectly.
  • Added F# examples in ortools/examples/fsharp. (Thanks to Matthew Moore).
  • Remove check for positive penalties in the routing library.


  1. Hi Perron, good job with or-tools.
    I have a question, is there a way to visualize the routes in the form of lines connecting the nodes whereby the nodes are labelled with the corresponding node numbers. Of course with each route having different color.

    Thank you

  2. Hi Laurent,

    I am new to Or-tools as well as python (I am using anaconda python 3.6), I am try to solve 20 Job-20 Machine scheduling problem, I am using the following benchmark data:

    I have many problems, one of them when i try to solve the problem of more than 10 M-10J, I have left python more than 12 hrs, and still overloaded.

    once again, when I have tried 15-M15J, I have the following error

    IndexError Traceback (most recent call last)
    in ()
    138 if __name__ == '__main__':
    --> 139 main()

    in main()
    46 horizon = 0
    47 for i in all_jobs:
    ---> 48 horizon += sum(processing_times[i])
    49 # Creates jobs.
    50 all_tasks = {}

    IndexError: list index out of range


Post a Comment

Popular posts from this blog

Heads up, upcoming incompatibility in the CP/Routing library

Changing the way we link with SCIP