Help regarding the fast-downward planner

[Drejer1]

So I have tried following the getting started guide, to solve problems. I have some solvable problems that works fine whenever I use the pyperplan engine but when I switch to fast-downward the problems becomes unsolvable for some reason. I have tried running the fast-downward planner outside of the unified-planning library on the problems and it works fine then. I'm pretty sure the engine is installed correctly, at least the credits show up when running the planner.
Looking at the docs https://unified-planning.readthedocs.io/en/latest/engines/3-fast_downward.html I'm not seeing anything I'm missing at least.

def check_if_solvable(problem: Problem):
    with OneshotPlanner(name='fast-downward') as planner:
        result = planner.solve(problem)
        if result.status == up.engines.PlanGenerationResultStatus.SOLVED_SATISFICING:
            # print("Pyperplan returned: %s" % result1.plan)
            return True
        else:
            print("No plan found.")
            return False

[Framba-Luca]

Hi @Drejer1 , can you provide some (or all) the problem examples? It really helps debugging 😃

In general, add all the code you can. Thank you very much!

[Framba-Luca]

Try finding the script build.py and run ./build.py release, as suggested in the error message.

[Drejer1]

I have multiple files called build.py, non of them atleast seems to be related to the fast-downward lib. There is not a script related to up-fast-downward in venv/scripts at all.
Running ./build.py release in the project paths which do contain a build.py
venv/Lib/site-packages/setuptools/command
venv/Lib/site-packages/setuptools/_distutils/command
just gives me ImportError: attempted relative import with no known parent package.

I have tried following the manual install on https://unified-planning.readthedocs.io/en/latest/engines/3-fast_downward.html skipping the first step since currently that link brings me to a dead page (which is weird since I'm pretty sure I looked at it a month or 2 ago) , but fast-downward works when I'm running that in terminal alone, so I assume the dependencies function. Doing it that way started giving me assertion errors when starting the program, so I discarded that idea.

I just noticed that when I'm installing pyperplan I get both a package named "pyperplan" and "up-pyperplan" while installing fast-downward I only get "up-fast-downward" I don't know if that means anything?

I will very much admit I am a novice at python, so I gotta ask. There is not anything from this page I'm missing is there? Something so obvious I am completely missing it? It really should just be writing pip install unified-planning[fast-downward]? So why am I missing the build.py related to fast-downward?

[Framba-Luca]

Is fast-downward the only engine you are having problems with?

@roeger Maybe you have seen this problem already?

[roeger]

Thanks for the heads up @Framba-Luca, I didn't see this before. This issue might be related to a bug in building the wheels for windows and was fixed in version 0.3.1 of up-fast-downward. @Drejer1, can you please install that version and try it?
pip install up-fast-downward==0.3.1

[Drejer1]

It works now, with the use of the 0.3.1 version.
Thank you for your help @Framba-Luca and @roeger

[arbimo]

Could you give the full print of result ? Note that there are several positive outcomes (e.g. SOLVED_OPTIMALLY) that may be associated with a plan. For a negative result, it would be also interesting to see the log of the planner probably (parameter output_stream=sys.stdout to the solve method).

[Drejer1]

Is this what you mean when you say full print of result?

status: INTERNAL_ERROR
engine: Fast Downward
plan: None

Using the parameter you gave gives this output.
I assume this might be the error here.

Usage: python implementation.py <path>
Could not find build 'release' at C:\Users\Drejer\PycharmProjects\PDDL_library_Tests\venv\lib\site-packages\up_fast_downward\downward\builds\release\bin. Please run './build.py release'.
INFO     planner time limit: None
INFO     planner memory limit: None

INFO     Running translator.