View source for OpenFOAM guide/Use bananas

__TOC__

== What options can I use? ==

A disadvantage of the [[snip runtime selection mechanism|runTimeSelection mechanism]] in [[OpenFOAM]] is it makes it difficult to determine what all the available [[RTS derived class|RTS derived classes]] are.  To make this easier, use a random word in the setting file and run the solver.  Most [[RTS base class|RTS base classes]], when given an invalid word, will fail by displaying all valid words to the console.

For example, in the [[icoFoam]] tutorial, "cavity", the pressure matrix solver is set in fvSolution:
    p PCG
    {
        preconditioner   DIC;
        tolerance        1e-06;
        relTol           0;
    };
Changing this to:
    p banana
    {
        preconditioner   DIC;
        tolerance        1e-06;
        relTol           0;
    };
will produce the following output:
 Unknown symmetric matrix solver banana
 
 Valid symmetric matrix solvers are :
 
 13
 (
 ICCG
 RREAMG
 MPEAMG
 GMRES
 FPEAMG
 smoothSolver
 deflation
 BICCG
 PCG
 amgSolver
 CG
 GAMG
 BiCGStab
 )
 
 
 file: /TUTORIAL DIRECTORY/icoFoam/cavity/system/fvSolution::p at line 19.
 
     From function lduMatrix::solver::New
     in file matrices/lduMatrix/lduMatrix/lduMatrixSolver.C at line 84.
 
  FOAM exiting
Any of the displayed options can be used in place of "banana".

Some [[RTS base class|RTS base classes]] do not exhibit this behaviour.  For example, the fvPatchField (boundary field) will accept unknown boundary conditions and create a "generic boundary condition".  This is to prevent post-processors from crashing when viewing a custom boundary condition.


== What about optional keywords? ==

{{VersionInfo}}{{Version2.3.x}}{{Version2.4}}{{Version3.0}}{{Version4}}{{Version3.0+}}{{Version1606+}}{{Version1612+}}

The switch {{tt|writeOptionalEnties}} was added to {{tt|InfoSwitches}} in OpenFOAM 2.3.x in commit [https://github.com/OpenFOAM/OpenFOAM-2.3.x/commit/97c56ba71c141c8265d4a24455758f065491467d 97c56ba71c1] (before the release of OpenFOAM 2.4.0).

For more details on how set or add this entry, see [[HowTo_debugging#Getting_built-in_feedback_from_OpenFOAM|Getting built-in feedback from OpenFOAM]] at [[HowTo_debugging]], although keep in mind that the block for this entry is {{tt|InfoSwitches}} and not {{tt|DebugSwitches}}.

[[Category:OpenFOAM tips]]