September release of or-tools

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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.

Comments

  1. UnknownOctober 4, 2017 at 8:43 AM

    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
    -
    Anthony

    ReplyDelete
  2. UnknownNovember 10, 2017 at 9:44 AM

    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: http://mistic.heig-vd.ch/taillard/problemes.dir/ordonnancement.dir/jobshop.dir/tai20_20.txt

    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 ()
    137
    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

    ReplyDelete
  3. UnknownJanuary 5, 2019 at 2:00 AM

    Which algorithm does OR-Tools use to solve Vehicle routing problems ?

    ReplyDelete
  4. UnknownJanuary 5, 2019 at 8:26 PM

    Hello Dr Laurent Perron:
    Merry Christmas and happy new year!
    　 I have concerned with operation research problems like vertex separation, minimum cost maximum flow for a long time. Currently I am doing research for supply chain financing project which provide services of factoring, forfaiting etc to customers, and I plan to design bipartite match engines between trade products to customers for each production stage, and another minimum cost maximum flow optimization solver to make most use of working capital in global view. I am very interested in Google's OR Tools which provided with some examples, and I believe we could carry out many valuable work under OR platform, so I would sincerely mail to Dr Laurent Perron to establish project connection.
    The supply chain financing project is working for a famous bank and will continue to invest and operate, I had admired OR abilities of French scientist for a long time, and I believe Dr Laurent Perron's help will be the rainbow that leads to success. I plan to visit Netherlands from Feb 13th,2019 to Feb 16th for Neo4j's graph modeling meeting. I am not sure if you still live in France or not, if you are still in Paris, I really hope to interview with Dr Laurent during this trip; if you are in Google Inc's Mountain View working place, I would plan to visit there some time in the near future.
    All in all , I am looking forward to hearing from you.
    My mail is : 1254209774@qq.com

    Best Regards
    Francis Huang
    Jan 5th, 2019
    Tongji University, Shanghai

    ReplyDelete
  5. UnknownJanuary 5, 2019 at 8:27 PM

    Hello Dr Laurent Perron:

    Merry Christmas and happy new year!

    　 I have concerned with operation research problems like vertex separation, minimum cost maximum flow for a long time. Currently I am doing research for supply chain financing project which provide services of factoring, forfaiting etc to customers, and I plan to design bipartite match engines between trade products to customers for each production stage, and another minimum cost maximum flow optimization solver to make most use of working capital in global view. I am very interested in Google's OR Tools which provided with some examples, and I believe we could carry out many valuable work under OR platform, so I would sincerely mail to Dr Laurent Perron to establish project connection.

    The supply chain financing project is working for a famous bank and will continue to invest and operate, I had admired OR abilities of French scientist for a long time, and I believe Dr Laurent Perron's help will be the rainbow that leads to success. I plan to visit Netherlands from Feb 13th,2019 to Feb 16th for Neo4j's graph modeling meeting. I am not sure if you still live in France or not, if you are still in Paris, I really hope to interview with Dr Laurent during this trip; if you are in Google Inc's Mountain View working place, I would plan to visit there some time in the near future.

    All in all , I am looking forward to hearing from you.
    My mail is : 1254209774@qq.com

    Best Regards
    Francis Huang
    Jan 5th, 2019
    Tongji University, Shanghai

    ReplyDelete

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