Points.h

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///////////////////////////////////////////////////////////////////////////////
//
// File: Points.hpp
//
// For more information, please see: http://www.nektar.info
//
// The MIT License
//
// Copyright (c) 2006 Division of Applied Mathematics, Brown University (USA),
// Department of Aeronautics, Imperial College London (UK), and Scientific
// Computing and Imaging Institute, University of Utah (USA).
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//
// Description: Header file of Points definition
//
///////////////////////////////////////////////////////////////////////////////
 
#ifndef NEKTAR_LIB_UTILITIES_FOUNDATIONS_POINTS_H
#define NEKTAR_LIB_UTILITIES_FOUNDATIONS_POINTS_H
 
#include <boost/core/ignore_unused.hpp>
 
#include <LibUtilities/BasicConst/NektarUnivTypeDefs.hpp>
#include <LibUtilities/Foundations/Foundations.hpp>
#include <LibUtilities/Foundations/FoundationsFwd.hpp>
#include <LibUtilities/LinearAlgebra/NekMatrixFwd.hpp>
 
//#include <LibUtilities/BasicUtils/BasicUtilsFwd.hpp>  // for NekManager
#include <LibUtilities/BasicUtils/ErrorUtil.hpp>
#include <LibUtilities/BasicUtils/SharedArray.hpp>
 
namespace Nektar
{
 
namespace LibUtilities
{
// Need to add method to compute total number of points given dimension
// and number of points.
 
/// Defines a specification for a set of points.
class PointsKey
{
public:
    // Used for looking up the creator. The creator for number of points
    // can generate for any number, so we want the same creator called
    // for all number.
    struct opLess
    {
        LIB_UTILITIES_EXPORT bool operator()(const PointsKey &lhs,
                                             const PointsKey &rhs) const;
    };
 
    /// Default constructor.
    PointsKey(void)
        : m_numpoints(0), m_pointstype(eNoPointsType),
          m_factor(NekConstants::kNekUnsetDouble)
    {
    }
 
    /// Constructor defining the number and distribution of points.
    PointsKey(const int &numpoints, const PointsType &pointstype,
              const NekDouble factor = NekConstants::kNekUnsetDouble)
        : m_numpoints(numpoints), m_pointstype(pointstype), m_factor(factor)
    {
    }
 
    /// Destructor.
    virtual ~PointsKey()
    {
    }
 
    /// Copy constructor.
    PointsKey(const PointsKey &key)
    {
        *this = key; // defer to assignment operator
    }
 
    PointsKey &operator=(const PointsKey &key)
    {
        m_numpoints  = key.m_numpoints;
        m_pointstype = key.m_pointstype;
        m_factor     = key.m_factor;
 
        return *this;
    }
 
    inline unsigned int GetNumPoints() const
    {
        return m_numpoints;
    }
 
    inline PointsType GetPointsType() const
    {
        return m_pointstype;
    }
 
    inline NekDouble GetFactor() const
    {
        return m_factor;
    }
 
    inline bool operator==(const PointsKey &key)
    {
 
        if (fabs(m_factor - key.m_factor) < NekConstants::kNekZeroTol)
        {
            return (m_numpoints == key.m_numpoints &&
                    m_pointstype == key.m_pointstype);
        }
 
        return false;
    }
 
    inline bool operator==(const PointsKey *y)
    {
        return (*this == *y);
    }
 
    inline bool operator!=(const PointsKey &y)
    {
        return (!(*this == y));
    }
 
    inline bool operator!=(const PointsKey *y)
    {
        return (!(*this == *y));
    }
 
    // If new points are added, this function must be modified
    inline unsigned int GetPointsDim() const
    {
        int dimpoints = 1;
 
        switch (m_pointstype)
        {
            case eNodalTriElec:
            case eNodalTriFekete:
            case eNodalTriEvenlySpaced:
            case eNodalTriSPI:
            case eNodalQuadElec:
                dimpoints = 2;
                break;
 
            case eNodalTetElec:
            case eNodalTetEvenlySpaced:
            case eNodalPrismEvenlySpaced:
            case eNodalPrismElec:
            case eNodalHexElec:
                dimpoints = 3;
                break;
 
            default:
                break;
        }
 
        return dimpoints;
    }
 
    // If new points are added, this function must be modified
    inline unsigned int GetTotNumPoints() const
    {
        int totpoints = m_numpoints;
 
        switch (m_pointstype)
        {
            case eNodalTriElec:
            case eNodalTriFekete:
            case eNodalTriEvenlySpaced:
                totpoints = m_numpoints * (m_numpoints + 1) / 2;
                break;
            case eNodalTriSPI:
                NEKERROR(ErrorUtil::efatal,
                         "This method cannot be implemented");
                break;
 
            case eNodalQuadElec:
                totpoints = m_numpoints * m_numpoints;
                break;
 
            case eNodalTetElec:
            case eNodalTetEvenlySpaced:
                totpoints =
                    m_numpoints * (m_numpoints + 1) * (m_numpoints + 2) / 6;
                break;
            case eNodalTetSPI:
                NEKERROR(ErrorUtil::efatal,
                         "This method cannot be implemented");
                break;
 
            case eNodalPrismEvenlySpaced:
            case eNodalPrismElec:
                totpoints = m_numpoints * m_numpoints * (m_numpoints + 1) / 2;
                break;
            case eNodalPrismSPI:
                NEKERROR(ErrorUtil::efatal,
                         "This method cannot be implemented");
                break;
 
            case eNodalHexElec:
                totpoints = m_numpoints * m_numpoints * m_numpoints;
                break;
 
            default:
                break;
        }
 
        return totpoints;
    }
 
    LIB_UTILITIES_EXPORT friend bool operator==(const PointsKey &lhs,
                                                const PointsKey &rhs);
    LIB_UTILITIES_EXPORT friend bool operator<(const PointsKey &lhs,
                                               const PointsKey &rhs);
    LIB_UTILITIES_EXPORT friend bool opLess::operator()(
        const PointsKey &lhs, const PointsKey &rhs) const;
 
protected:
    unsigned int m_numpoints; //!< number of the points (as appropriately
                              //!< defined for PointsType)
    PointsType m_pointstype;  //!< Type of Points
    NekDouble m_factor;       //!< optional factor
private:
};
 
static const PointsKey NullPointsKey(0, eNoPointsType);
 
LIB_UTILITIES_EXPORT bool operator==(const PointsKey &lhs,
                                     const PointsKey &rhs);
LIB_UTILITIES_EXPORT bool operator<(const PointsKey &lhs, const PointsKey &rhs);
LIB_UTILITIES_EXPORT std::ostream &operator<<(std::ostream &os,
                                              const PointsKey &rhs);
 
typedef std::vector<PointsKey> PointsKeyVector;
 
/// Stores a set of points of datatype DataT, defined by a PointKey.
template <typename DataT> class Points
{
public:
    typedef DataT DataType;
    typedef std::shared_ptr<NekMatrix<DataType>> MatrixSharedPtrType;
 
    virtual ~Points()
    {
    }
 
    virtual void Initialize(void)
    {
        CalculatePoints();
        CalculateWeights();
        CalculateBaryWeights();
        CalculateDerivMatrix();
    }
 
    inline unsigned int GetPointsDim() const
    {
        return m_pointsKey.GetPointsDim();
    }
 
    inline unsigned int GetNumPoints() const
    {
        return m_pointsKey.GetNumPoints();
    }
 
    inline unsigned int GetTotNumPoints() const
    {
        return m_pointsKey.GetTotNumPoints();
    }
 
    inline PointsType GetPointsType() const
    {
        return m_pointsKey.GetPointsType();
    }
 
    inline const Array<OneD, const DataType> &GetZ() const
    {
        return m_points[0];
    }
 
    inline const Array<OneD, const DataType> &GetW() const
    {
        return m_weights;
    }
 
    inline void GetZW(Array<OneD, const DataType> &z,
                      Array<OneD, const DataType> &w) const
    {
        z = m_points[0];
        w = m_weights;
    }
 
    inline const Array<OneD, const NekDouble> &GetBaryWeights() const
    {
        return m_bcweights;
    }
 
    inline void GetPoints(Array<OneD, const DataType> &x) const
    {
        x = m_points[0];
    }
 
    inline void GetPoints(Array<OneD, const DataType> &x,
                          Array<OneD, const DataType> &y) const
    {
        x = m_points[0];
        y = m_points[1];
    }
 
    inline void GetPoints(Array<OneD, const DataType> &x,
                          Array<OneD, const DataType> &y,
                          Array<OneD, const DataType> &z) const
    {
        x = m_points[0];
        y = m_points[1];
        z = m_points[2];
    }
 
    inline const MatrixSharedPtrType &GetD(Direction dir = xDir) const
    {
        return m_derivmatrix[(int)dir];
    }
 
    virtual const MatrixSharedPtrType GetI(const PointsKey &key)
    {
        boost::ignore_unused(key);
        NEKERROR(ErrorUtil::efatal, "Method not implemented ");
        std::shared_ptr<NekMatrix<NekDouble>> returnval(
            MemoryManager<NekMatrix<NekDouble>>::AllocateSharedPtr());
        return returnval;
    }
 
    virtual const MatrixSharedPtrType GetI(const Array<OneD, const DataType> &x)
    {
        boost::ignore_unused(x);
        NEKERROR(ErrorUtil::efatal, "Method not implemented");
        std::shared_ptr<NekMatrix<NekDouble>> returnval(
            MemoryManager<NekMatrix<NekDouble>>::AllocateSharedPtr());
        return returnval;
    }
 
    virtual const MatrixSharedPtrType GetI(unsigned int,
                                           const Array<OneD, const DataType> &x)
    {
        boost::ignore_unused(x);
        NEKERROR(ErrorUtil::efatal, "Method not implemented");
        std::shared_ptr<NekMatrix<NekDouble>> returnval(
            MemoryManager<NekMatrix<NekDouble>>::AllocateSharedPtr());
        return returnval;
    }
 
    virtual const MatrixSharedPtrType GetI(const Array<OneD, const DataType> &x,
                                           const Array<OneD, const DataType> &y)
    {
        boost::ignore_unused(x, y);
        NEKERROR(ErrorUtil::efatal, "Method not implemented");
        std::shared_ptr<NekMatrix<NekDouble>> returnval(
            MemoryManager<NekMatrix<NekDouble>>::AllocateSharedPtr());
        return returnval;
    }
 
    virtual const MatrixSharedPtrType GetI(const Array<OneD, const DataType> &x,
                                           const Array<OneD, const DataType> &y,
                                           const Array<OneD, const DataType> &z)
    {
        boost::ignore_unused(x, y, z);
        NEKERROR(ErrorUtil::efatal, "Method not implemented");
        std::shared_ptr<NekMatrix<NekDouble>> returnval(
            MemoryManager<NekMatrix<NekDouble>>::AllocateSharedPtr());
        return returnval;
    }
 
    virtual const MatrixSharedPtrType GetGalerkinProjection(
        const PointsKey &pkey)
    {
        boost::ignore_unused(pkey);
        NEKERROR(ErrorUtil::efatal, "Method not implemented ");
        std::shared_ptr<NekMatrix<NekDouble>> returnval(
            MemoryManager<NekMatrix<NekDouble>>::AllocateSharedPtr());
        return returnval;
    }
 
protected:
    /// Points type for this points distributions.
    PointsKey m_pointsKey;
    /// Storage for the point locations, allowing for up to a 3D points
    /// storage.
    Array<OneD, DataType> m_points[3];
    /// Quadrature weights for the weights.
    Array<OneD, DataType> m_weights;
    /// Barycentric weights.
    Array<OneD, DataType> m_bcweights;
    /// Derivative matrices.
    MatrixSharedPtrType m_derivmatrix[3];
    NekManager<PointsKey, NekMatrix<DataType>, PointsKey::opLess>
        m_InterpManager;
    NekManager<PointsKey, NekMatrix<DataType>, PointsKey::opLess>
        m_GalerkinProjectionManager;
 
    virtual void CalculatePoints()
    {
        unsigned int pointsDim    = GetPointsDim();
        unsigned int totNumPoints = GetTotNumPoints();
 
        for (unsigned int i = 0; i < pointsDim; ++i)
        {
            m_points[i] = Array<OneD, DataType>(totNumPoints);
        }
    }
 
    virtual void CalculateWeights()
    {
        m_weights = Array<OneD, DataType>(GetTotNumPoints());
    }
 
    /**
     * @brief This function calculates the barycentric weights used for
     * enhanced interpolation speed.
     *
     * For the points distribution \f$ z_i \f$ with \f% 1\leq z_i \leq N
     * \f$, the barycentric weights are computed as:
     *
     * \f[
     * b_i=\prod_{\substack{1\leq j\leq N\\ i\neq j}} \frac{1}{z_i-z_j}
     * \f]
     */
    virtual void CalculateBaryWeights()
    {
        const unsigned int totNumPoints = m_pointsKey.GetNumPoints();
        m_bcweights = Array<OneD, DataType>(totNumPoints, 1.0);
 
        Array<OneD, DataType> z = m_points[0];
 
        for (unsigned int i = 0; i < totNumPoints; ++i)
        {
            for (unsigned int j = 0; j < totNumPoints; ++j)
            {
                if (i == j)
                {
                    continue;
                }
 
                m_bcweights[i] *= (z[i] - z[j]);
            }
 
            m_bcweights[i] = 1.0 / m_bcweights[i];
        }
    }
 
    virtual void CalculateDerivMatrix()
    {
        int totNumPoints = GetTotNumPoints();
        for (unsigned int i = 0; i < m_pointsKey.GetPointsDim(); ++i)
        {
            m_derivmatrix[i] =
                MemoryManager<NekMatrix<DataType>>::AllocateSharedPtr(
                    totNumPoints, totNumPoints);
        }
    }
 
    Points(const PointsKey &key) : m_pointsKey(key)
    {
    }
 
private:
    // These should never be called
    Points(const Points &pts)
    {
        boost::ignore_unused(pts);
        NEKERROR(ErrorUtil::efatal,
                 "Copy Constructor for Points should not be called");
    }
    Points()
    {
        NEKERROR(ErrorUtil::efatal,
                 "Default Constructor for Points should not be called");
    }
};
 
} // namespace LibUtilities
} // namespace Nektar
 
#endif // NEKTAR_LIB_UTILITIES_FOUNDATIONS_POINTS_H