DistributedVector.hpp

/*

Copyright (C) University of Oxford, 2005-2011

University of Oxford means the Chancellor, Masters and Scholars of the
University of Oxford, having an administrative office at Wellington
Square, Oxford OX1 2JD, UK.

This file is part of Chaste.

Chaste is free software: you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation, either version 2.1 of the License, or
(at your option) any later version.

Chaste is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
License for more details. The offer of Chaste under the terms of the
License is subject to the License being interpreted in accordance with
English Law and subject to any action against the University of Oxford
being under the jurisdiction of the English Courts.

You should have received a copy of the GNU Lesser General Public License
along with Chaste. If not, see <http://www.gnu.org/licenses/>.

*/


#ifndef DISTRIBUTEDVECTOR_HPP_
#define DISTRIBUTEDVECTOR_HPP_

#include <vector>
#include <petscvec.h>
#include <iostream>
#include <cassert>

#include "DistributedVectorException.hpp"

class DistributedVectorFactory;

class DistributedVector
{
private:
    friend class TestDistributedVector;

    // Data global to all vectors

    unsigned mLo;

    unsigned mHi;

    unsigned mProblemSize;

    // Data local to a single vector

    unsigned mSizeMultiplier;

    Vec mVec;

    double* mpVec;

    DistributedVectorFactory* mpFactory;

public:

    bool IsGlobalIndexLocal(unsigned globalIndex);

    DistributedVector(Vec vec, DistributedVectorFactory* pFactory);

    unsigned GetHigh() const
    {
        return mHi;
    }

    unsigned GetLow() const
    {
        return mLo;
    }

    DistributedVectorFactory* GetFactory()
    {
        return mpFactory;
    }

    double& operator[](unsigned globalIndex) throw (DistributedVectorException);

    void Restore();

    class Iterator
    {
    public:
        unsigned Local;  
        unsigned Global; 
        bool operator!=(const Iterator& rOther);

        Iterator& operator++();
    };

    class Stripe
    {
        unsigned mStride; 
        unsigned mStripe; 
        double* mpVec;    
        unsigned mLo;     
        unsigned mHi;     
        DistributedVectorFactory* mpFactory; 
    public:
        Stripe(DistributedVector parallelVec, unsigned stripe)
        {
            mStride = parallelVec.mSizeMultiplier;
            mStripe = stripe;
            assert(mStripe < mStride);
            mpVec = parallelVec.mpVec;
            mLo = parallelVec.GetLow();
            mHi = parallelVec.GetHigh();
            mpFactory = parallelVec.GetFactory();
        }

        DistributedVectorFactory* GetFactory()
        {
            return mpFactory;
        }

        double& operator[](unsigned globalIndex) throw (DistributedVectorException)
        {
            if (mLo <= globalIndex && globalIndex < mHi)
            {
                return mpVec[(globalIndex - mLo)*mStride + mStripe];
            }
            throw DistributedVectorException();
        }

        double& operator[](Iterator index) throw (DistributedVectorException)
        {
            return mpVec[index.Local*mStride + mStripe];
        }

    };

    class Chunk
    {
        unsigned mOffset; 
        double* mpVec;    
        unsigned mLo;     
        unsigned mHi;     
    public:
        Chunk(DistributedVector parallelVec, unsigned chunk)
        {
            assert(chunk < parallelVec.mSizeMultiplier);
            mLo = parallelVec.GetLow();
            mHi = parallelVec.GetHigh();
            mOffset = chunk * (mHi - mLo);
            mpVec = parallelVec.mpVec;
        }

        double& operator[](unsigned globalIndex) throw (DistributedVectorException)
        {
            if (mLo <= globalIndex && globalIndex < mHi)
            {
                //localIndex = globalIndex - mLo
                return mpVec[mOffset + globalIndex - mLo];
            }
            throw DistributedVectorException();
         }

        double& operator[](Iterator index) throw (DistributedVectorException)
        {
            return mpVec[mOffset + index.Local];
        }

    };

    Iterator Begin();

    Iterator End();

    double& operator[](Iterator index) throw (DistributedVectorException);
};

#endif /*DISTRIBUTEDVECTOR_HPP_*/