Fast Downward has been in development since 2003, but the current timed release model was not adopted until 2019. This file documents the changes since the first timed release, Fast Downward 19.06.
For more details, check the repository history (http://hg.fast-downward.org) and the issue tracker (http://issues.fast-downward.org). Repository branches are named after the corresponding tracker issues.
-
Integrate new pruning method
atom_centric_stubborn_sets()http://issues.fast-downward.org/issue781 We merged the code for the SoCS 2020 paper "An Atom-Centric Perspective on Stubborn Sets" (https://ai.dmi.unibas.ch/papers/roeger-et-al-socs2020.pdf). -
Fix
--show-aliasesparameter. -
OptionParser: make OptionParser::add_enum_option templated and remove Options::get_enum http://issues.fast-downward.org/issue962 We now store enum options as enums instead of as ints in Options objects.
-
Use global logging mechanism for all output http://issues.fast-downward.org/issue963 All output of the planner is now handled by a global logging mechnism, which prefaces printed lines with time and memory information. For developers, this means that output is no longer passed to cout, but utils::g_log.
-
For developers: allow creating Timers in stopped state http://issues.fast-downward.org/issue965
Released on December 20, 2019.
Highlights:
-
Fast Downward no longer supports Python 2.7, which reaches its end of support on January 1, 2020. The minimum supported Python version is now 3.6.
-
Fast Downward now supports the SoPlex LP solver.
Details:
-
general: raise minimum supported Python version to 3.6 http://issues.fast-downward.org/issue939 Fast Downward now requires Python 3.6 or newer; support for Python 2.7 and Python 3.2-3.5 has been dropped. The main reason for this change is Python 2 reaching its end of support on January 1, 2020. See https://python3statement.org/ for more background.
-
LP solver: add support for the solver SoPlex http://issues.fast-downward.org/issue752 The relative performance of CPLEX and SoPlex depends on the domain and configuration with each solver outperforming the other in some cases. See the issue for a more detailed discussion of performance.
-
LP solver: add support for version 12.9 of CPLEX http://issues.fast-downward.org/issue925 Older versions are still supported but we recommend using 12.9. In our experiments, we saw performance differences between version 12.8 and 12.9, as well as between using static and dynamic linking. However, on average there was no significant advantage for any configuration. See the issue for details.
-
LP solver: update build instructions of the open solver interface http://issues.fast-downward.org/issue752 http://issues.fast-downward.org/issue925 The way we recommend building OSI now links dynamically against the solvers and uses zlib. If your existing OSI installation stops working, try installing zlib (sudo apt install zlib1g-dev) or re-install OSI (http://www.fast-downward.org/LPBuildInstructions).
-
merge-and-shrink: remove trivial factors http://issues.fast-downward.org/issue914 When the merge-and-shrink computation terminates with several factors (due to using a time limit), only keep those factors that are non-trivial, i.e., which have a non-goal state or which represent a non-total function.
-
tests: use pytest for running most tests http://issues.fast-downward.org/issue935 http://issues.fast-downward.org/issue936
-
tests: test Python code with all supported Python versions using tox http://issues.fast-downward.org/issue930
-
tests: adjust style of Python code as suggested by flake8 and add this style check to the continuous integration test suite http://issues.fast-downward.org/issue929 http://issues.fast-downward.org/issue931 http://issues.fast-downward.org/issue934
-
scripts: move Stone Soup generator scripts to separate repository at https://github.com/aibasel/stonesoup. http://issues.fast-downward.org/issue932
Released on June 11, 2019. First time-based release.