ptscotchDecomp.H

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License
    This file is part of OpenFOAM.
 
    OpenFOAM is free software: you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
 
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    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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    You should have received a copy of the GNU General Public License
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Class
    Foam::ptscotchDecomp
 
Description
    PTScotch domain decomposition.
    For the main details about how to define the strategies, see scotchDecomp.
 
    Nonetheless, when decomposing in parallel, using <tt>writeGraph=true</tt>
    will write out \c .dgr files for debugging. For example, use these files
    with \c dgpart as follows:
 
    \verbatim
    mpirun -np 4 dgpart 2 'region0_%r.dgr'
    \endverbatim
 
    where:
      - %r gets replaced by current processor rank
      - it will decompose into 2 domains
 
See also
    Foam::scotchDecomp
 
SourceFiles
    ptscotchDecomp.C
 
\*---------------------------------------------------------------------------*/
 
#ifndef ptscotchDecomp_H
#define ptscotchDecomp_H
 
#include "decompositionMethod.H"
 
namespace Foam
{
 
/*---------------------------------------------------------------------------*\
                       Class ptscotchDecomp Declaration
\*---------------------------------------------------------------------------*/
 
class ptscotchDecomp
:
    public decompositionMethod
{
    // Private Member Functions
 
        //- Check and print error message
        static void check(const int, const char*);
 
        //- Decompose. Handles size 0 arrays
        label decompose
        (
            const fileName& meshPath,
            const List<label>& adjncy,
            const List<label>& xadj,
            const scalarField& cWeights,
            List<label>& finalDecomp
        ) const;
 
        //- Low level decompose
        label decompose
        (
            const fileName& meshPath,
            const label adjncySize,
            const label adjncy[],
            const label xadjSize,
            const label xadj[],
            const scalarField& cWeights,
            List<label>& finalDecomp
        ) const;
 
 
public:
 
    //- Runtime type information
    TypeName("ptscotch");
 
 
    // Constructors
 
        //- Construct given the decomposition dictionary and mesh
        ptscotchDecomp(const dictionary& decompositionDict);
 
        //- Disallow default bitwise copy construction
        ptscotchDecomp(const ptscotchDecomp&) = delete;
 
 
    //- Destructor
    virtual ~ptscotchDecomp()
    {}
 
 
    // Member Functions
 
        //- Inherit decompose from decompositionMethod
        using decompositionMethod::decompose;
 
        //- Return for every coordinate the wanted processor number. Use the
        //  mesh connectivity (if needed). See note on weights in scotchDecomp.H
        virtual labelList decompose
        (
            const polyMesh& mesh,
            const pointField& points,
            const scalarField& pointWeights
        );
 
        //- Return for every coordinate the wanted processor number. Gets
        //  passed agglomeration map (from fine to coarse cells) and coarse cell
        //  location. Can be overridden by decomposers that provide this
        //  functionality natively. See note on weights in scotchDecomp.H
        virtual labelList decompose
        (
            const polyMesh& mesh,
            const labelList& agglom,
            const pointField& regionPoints,
            const scalarField& regionWeights
        );
 
        //- Return for every coordinate the wanted processor number. Explicitly
        //  provided mesh connectivity.
        //  The connectivity is equal to mesh.cellCells() except for
        //  - in parallel the cell numbers are global cell numbers (starting
        //    from 0 at processor0 and then incrementing all through the
        //    processors)
        //  - the connections are across coupled patches
        //  See note on weights in scotchDecomp.H
        virtual labelList decompose
        (
            const labelListList& globalCellCells,
            const pointField& cc,
            const scalarField& cWeights
        );
 
 
    // Member Operators
 
        //- Disallow default bitwise assignment
        void operator=(const ptscotchDecomp&) = delete;
};
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace Foam
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#endif
 
// ************************************************************************* //