MomentumSpaceContext.h

/* Copyright 2017 Kristofer Björnson
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


#ifndef COM_DAFER45_TBTK_RPA_MOMENTUM_SPACE_CONTEXT
#define COM_DAFER45_TBTK_RPA_MOMENTUM_SPACE_CONTEXT

#include "TBTK/BrillouinZone.h"
#include "TBTK/Solver/BlockDiagonalizer.h"
#include "TBTK/PropertyExtractor/BlockDiagonalizer.h"

namespace TBTK{
namespace RPA{

class MomentumSpaceContext{
public:
    MomentumSpaceContext();

    ~MomentumSpaceContext();

    void setModel(Model &model);

    const Model& getModel() const;

    void setBrillouinZone(const BrillouinZone &brillouinZone);

    const BrillouinZone& getBrillouinZone() const;

    void setNumMeshPoints(const std::vector<unsigned int> &numMeshPoints);

    const std::vector<unsigned int>& getNumMeshPoints() const;

    const std::vector<std::vector<double>>& getMesh() const;

    void setNumOrbitals(unsigned int numOrbitals);

    unsigned int getNumOrbitals() const;

    void init();

    double getEnergy(unsigned int state) const;

    double getEnergy(unsigned int block, unsigned int state) const;

    std::complex<double> getAmplitude(
        unsigned int block,
        unsigned int state,
        unsigned int amplitude
    ) const;

    Index getKIndex(const std::vector<double> &k) const;

    const PropertyExtractor::BlockDiagonalizer& getPropertyExtractorBlockDiagonalizer() const;
private:
    Model *model;

    const BrillouinZone *brillouinZone;

    std::vector<unsigned int> numMeshPoints;

    std::vector<std::vector<double>> mesh;

    unsigned int numOrbitals;

    Solver::BlockDiagonalizer solver;

    PropertyExtractor::BlockDiagonalizer *propertyExtractor;

    double *energies;

    std::complex<double> *amplitudes;

    bool isInitialized;

};

inline void MomentumSpaceContext::setModel(Model &model){
    this->model = &model;

    isInitialized = false;
}

inline const Model& MomentumSpaceContext::getModel() const{
    return *model;
}

inline void MomentumSpaceContext::setBrillouinZone(
    const BrillouinZone &brillouinZone
){
    this->brillouinZone = &brillouinZone;

    isInitialized = false;
}

inline const BrillouinZone& MomentumSpaceContext::getBrillouinZone() const{
    return *brillouinZone;
}

inline void MomentumSpaceContext::setNumMeshPoints(
    const std::vector<unsigned int> &numMeshPoints
){
    this->numMeshPoints = numMeshPoints;
    TBTKAssert(
        brillouinZone != nullptr,
        "MomentumSpaceContext::setNumMeshPoints()",
        "BrillouinZone not set.",
        "First set the BrillouinZone using"
        << " MomentumSpaceContext::setBrillouinZone()"
    );
    mesh = brillouinZone->getMinorMesh(numMeshPoints);

    isInitialized = false;
}

inline const std::vector<unsigned int>& MomentumSpaceContext::getNumMeshPoints(
) const{
    return numMeshPoints;
}

inline const std::vector<std::vector<double>>& MomentumSpaceContext::getMesh(
) const{
    return mesh;
}

inline void MomentumSpaceContext::setNumOrbitals(unsigned int numOrbitals){
    this->numOrbitals = numOrbitals;

    isInitialized = false;
}

inline unsigned int MomentumSpaceContext::getNumOrbitals() const{
    return numOrbitals;
}

inline double MomentumSpaceContext::getEnergy(unsigned int state) const{
    return energies[state];
}

inline double MomentumSpaceContext::getEnergy(
    unsigned int block,
    unsigned int state
) const{
    return energies[block*numOrbitals + state];
}

inline std::complex<double> MomentumSpaceContext::getAmplitude(
    unsigned int block,
    unsigned int state,
    unsigned int amplitude
) const{
    return amplitudes[numOrbitals*(numOrbitals*block + state) + amplitude];
}

inline Index MomentumSpaceContext::getKIndex(
    const std::vector<double> &k
) const{
    return brillouinZone->getMinorCellIndex(
        k,
        numMeshPoints
    );
}

inline const PropertyExtractor::BlockDiagonalizer& MomentumSpaceContext::getPropertyExtractorBlockDiagonalizer(
) const{
    return *propertyExtractor;
}

};  //End of namespace RPA
};  //End of namespace TBTK

#endif