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We’re happy to announce the release of July 2016 version of or-tools. Here's what's new with this release:
Constraint solver:
  • Routing
    • A disjunction can now be defined with a cardinality, which is the maximum number of nodes that can be active within this disjunction. For example, if you add a disjunction with n nodes and a cardinality of k, then k nodes among the n nodes are allowed to be active. You can use the new definition of AddDisjunction to do this.
    • Added support for multiple disjunctions per node. For example, you can now add a node, N1, to many disjunctions (D1..Dm). This increases its chance of being active within any one of them.
    • Introduced a faster routing search algorithm for problems related to disjunct time windows.
    • Added constraint solver parameters to routing model parameters and log_search to routing search parameters.
    • Local search algorithm is faster with resolving problems with disjoint time windows. Please see cvrp_disjoint_tw.cc example.
Glop (linear optimization):
  • Introduced a faster Simplex Algorithm.
Or-tools distribution:

  • One archive per platform, rather than individual archives for each of C++, Java, and C#. Python archives are still hosted on pypi.
  • On pypi, we have switched to wheel (.whl) modules on Mac OS X and Windows.
  • Introduced a MAJOR.MINOR numbering schema. These numbers are used the archive names, the version stored in Mac OS X shared libraries, python modules, .NET assemblies. The first version we are releasing is with this schema is v4.2.

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