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Pyomo with octeract - Failed to create solver with name 'octeract-engine'

When trying to use octeract with pyomo, I uncounter the following error.

2022-06-22 15:48:44,451 [ WARNING][pyomo.opt] Failed to create solver with name 'octeract-engine':
Failed to set executable for solver asl. File with name=octeract-engine either does not exist or it is not executable. To skip this validation, call set_executable with validate=False.

[...]

The SolverFactory was unable to create the solver "octeract-engine"
and returned an UnknownSolver object.  This error is raised at the point
where the UnknownSolver object was used as if it were valid (by calling
method "solve").

The original solver was created with the following parameters:
        executable: octeract-engine
        type: octeract-engine
        _args: ()
        options: {}

I've tried following both octerat doc and this doc unsuccessfully.

Solution

  • This is the classic Pyomo message when the binary it's told to invoke (in this case octeract-engine) is not in the system PATH.

    You can fix this by adding the engine to the PATH. The way to verify that this was done correctly is to start up the terminal that you use to invoke Pyomo (e.g. linux terminal or powershell), and type octeract-engine (linux) or octeract-engine.exe (windows). If the engine is in the PATH, this will print the engine's help menu, otherwise the system will complain that the binary was not found.

    What's actually happening here is that Octeract Engine connects to Pyomo through an ASL interface. Pyomo simply looks for a binary in the system PATH with the "name" specified in the command. As long as that binary has an ASL interface, it will just work, however Pyomo leaves it up to the user to ensure that the binary is visible in the PATH.

    Our installers actually add the binary to the PATH on all platforms by default for this reason, so try a clean reinstall and see if that fixes your issue. Otherwise, it's likely that you don't have the right permissions set up on your machine i.e., the Python version that runs Pyomo doesn't see the right PATH (e.g. if you use octeract-engine.exe on powershell but run Pyomo from cmd.exe).