google/or-tools v9.7

v9.7 (2023/08)

on GitHub

Platforms

• Drop Fedora [33,36] (EOL).
• Drop Centos 8.
• Drop Debian 10.
• Drop Ubuntu 18.04 LTS.
• Drop Python 3.7 support (EOL).
• Disable .Net Core 3.1 (EOL)

Dependencies

• ZLIB 1.2.13.
• abseil-cpp 20230125.3.
• Protobuf v21.12 -> v23.3.
• re2 2023-07-01.
• googletest v1.13.0.
• Java JNA 5.12.1 -> 5.13.0.

Bazel

• Require Bazel 6+.
• Update rules, fix build.
  • rules_jvm_external: 4.5 -> 5.2
  • contrib_rules_jvm: 0.9.0 -> 0.9.0
  • rules_python: 0.20.0 -> 0.23.1

Graphs

• Deep Rework.

Model Builder python

• Allow use of Pandas dataframes and series to create variables.
  • see assignment
  • see bin_packing
• Complete typing information

PDLP

• various update.

CP-SAT

• Performance improvements. (feasibility_jump, lin_max)
• Improve cut management
• New objective_shaving_search worker dedicated to improving the lower bound of the objective (when minimizing)
• Typing annotations for the python cp_model.py
• Experimental partial support for pandas in cp_model.py
  • see assignment
  • see bin_packing
• Experimental local search violation based workers:
  • enabled with parameters: num_violation_ls:xxx
  • optimized for linear model (linear, bool_or, bool_and, at_most_one, exactly_one)
  • works correctly with lin_max, product, division
  • supports no_overlap, cumulative, circuit, routes
  • disabled with no_overlap_2d
  • recommended number of ls workers: num_workers -> num_violation_ls (8, 1), (16, 2) (24, 3), (32, 4)

What's Changed

• Ignore the close error when reading fails in file.cc by @ciarand in #3717
• Fix reference to solve_wrapper in Solve method by @djsilcock in #3719
• ensure absolute native library path in Java Loader by @afloren in #3728
• Allow last_variable_index_ to be zero by @rajgoel in #3758
• Xpress fixes by @djunglas in #3576
• Update cplex_interface.cc by @Robot-1x in #3764 #3766
• feat(python): unignore Solver::TopProgressPercent and SearchMonitor::… by @bertuccellimatteo in #3831
• Evaluate LinearExp for the found solution by @koen-lee in #3837
• Fix CMake build in test subdirectories by @lnikkila in #3845
• Python CP-SAT type hints by @stradivari96 in #3668
• Fix RUNPATHs for libraries and executables by @StefanBruens in #3383

New Contributors

• @ciarand made their first contribution in #3717
• @djsilcock made their first contribution in #3719
• @afloren made their first contribution in #3728
• @rajgoel made their first contribution in #3758
• @djunglas made their first contribution in #3576
• @Robot-1x made their first contribution in #3764
• @bertuccellimatteo made their first contribution in #3831

Full Changelog: v9.6...v9.7