// This file is part of Eigen, a lightweight C++ template library
// for linear algebra. Eigen itself is part of the KDE project.
//
// Copyright (C) 2006-2008 Benoit Jacob <jacob@math.jussieu.fr>
//
// Eigen 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 3 of the License, or (at your option) any later version.
//
// Alternatively, 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 2 of
// the License, or (at your option) any later version.
//
// Eigen 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 or the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License and a copy of the GNU General Public License along with
// Eigen. If not, see <http://www.gnu.org/licenses/>.

#ifndef EIGEN_MATRIXBASE_H
#define EIGEN_MATRIXBASE_H

/** \class MatrixBase
  *
  * \brief Base class for all matrices, vectors, and expressions
  *
  * This class is the base that is inherited by all matrix, vector, and expression
  * types. Most of the Eigen API is contained in this class.
  *
  * \param Derived is the derived type, e.g. a matrix type, or an expression, etc.
  *
  * When writing a function taking Eigen objects as argument, if you want your function
  * to take as argument any matrix, vector, or expression, just let it take a
  * MatrixBase argument. As an example, here is a function printFirstRow which, given
  * a matrix, vector, or expression \a x, prints the first row of \a x.
  *
  * \code
    template<typename Derived>
    void printFirstRow(const Eigen::MatrixBase<Derived>& x)
    {
      cout << x.row(0) << endl;
    }
  * \endcode
  *
  * \nosubgrouping
  */
template<typename Derived> class MatrixBase : public ArrayBase<Derived>
{
    struct CommaInitializer;

  public:

    typedef typename ei_traits<Derived>::Scalar Scalar;
    typedef typename ei_packet_traits<Scalar>::type PacketScalar;

    enum {

      RowsAtCompileTime
        /**< The number of rows at compile-time. This is just a copy of the value provided
          * by the \a Derived type. If a value is not known at compile-time,
          * it is set to the \a Dynamic constant.
          * \sa MatrixBase::rows(), MatrixBase::cols(), ColsAtCompileTime, SizeAtCompileTime */
        = ei_traits<Derived>::RowsAtCompileTime,

     ColsAtCompileTime
        /**< The number of columns at compile-time. This is just a copy of the value provided
          * by the \a Derived type. If a value is not known at compile-time,
          * it is set to the \a Dynamic constant.
          * \sa MatrixBase::rows(), MatrixBase::cols(), RowsAtCompileTime, SizeAtCompileTime */
        = ei_traits<Derived>::ColsAtCompileTime,

      SizeAtCompileTime
        /**< This is equal to the number of coefficients, i.e. the number of
          * rows times the number of columns, or to \a Dynamic if this is not
          * known at compile-time. \sa RowsAtCompileTime, ColsAtCompileTime */
        = ei_size_at_compile_time<ei_traits<Derived>::RowsAtCompileTime,
                                  ei_traits<Derived>::ColsAtCompileTime>::ret,

      MaxRowsAtCompileTime
        /**< This value is equal to the maximum possible number of rows that this expression
          * might have. If this expression might have an arbitrarily high number of rows,
          * this value is set to \a Dynamic.
          *
          * This value is useful to know when evaluating an expression, in order to determine
          * whether it is possible to avoid doing a dynamic memory allocation.
          *
          * \sa RowsAtCompileTime, MaxColsAtCompileTime, MaxSizeAtCompileTime
          */
        = ei_traits<Derived>::MaxRowsAtCompileTime,

      MaxColsAtCompileTime
        /**< This value is equal to the maximum possible number of columns that this expression
          * might have. If this expression might have an arbitrarily high number of columns,
          * this value is set to \a Dynamic.
          *
          * This value is useful to know when evaluating an expression, in order to determine
          * whether it is possible to avoid doing a dynamic memory allocation.
          *
          * \sa ColsAtCompileTime, MaxRowsAtCompileTime, MaxSizeAtCompileTime
          */
        = ei_traits<Derived>::MaxColsAtCompileTime,

      MaxSizeAtCompileTime
        /**< This value is equal to the maximum possible number of coefficients that this expression
          * might have. If this expression might have an arbitrarily high number of coefficients,
          * this value is set to \a Dynamic.
          *
          * This value is useful to know when evaluating an expression, in order to determine
          * whether it is possible to avoid doing a dynamic memory allocation.
          *
          * \sa SizeAtCompileTime, MaxRowsAtCompileTime, MaxColsAtCompileTime
          */
        = ei_size_at_compile_time<ei_traits<Derived>::MaxRowsAtCompileTime,
                                                     ei_traits<Derived>::MaxColsAtCompileTime>::ret,

      IsVectorAtCompileTime
        /**< This is set to true if either the number of rows or the number of
          * columns is known at compile-time to be equal to 1. Indeed, in that case,
          * we are dealing with a column-vector (if there is only one column) or with
          * a row-vector (if there is only one row). */
        = ei_traits<Derived>::RowsAtCompileTime == 1 || ei_traits<Derived>::ColsAtCompileTime == 1,

      Flags
        /**< This stores expression metadata which typically is inherited by new expressions
          * constructed from this one. The available flags are FIXME!!! document that !!!
          */
        = ei_traits<Derived>::Flags,

      CoeffReadCost
        /**< This is a rough measure of how expensive it is to read one coefficient from
          * this expression.
          */
        = ei_traits<Derived>::CoeffReadCost
    };

    /** Default constructor. Just checks at compile-time for self-consistency of the flags. */
    MatrixBase()
    {
      ei_assert(ei_are_flags_consistent<Flags>::ret);
    }

    /** This is the "real scalar" type; if the \a Scalar type is already real numbers
      * (e.g. int, float or double) then \a RealScalar is just the same as \a Scalar. If
      * \a Scalar is \a std::complex<T> then RealScalar is \a T.
      *
      * In fact, \a RealScalar is defined as follows:
      * \code typedef typename NumTraits<Scalar>::Real RealScalar; \endcode
      *
      * \sa class NumTraits
      */
    typedef typename NumTraits<Scalar>::Real RealScalar;

    /** \returns the number of rows. \sa cols(), RowsAtCompileTime */
    inline int rows() const { return derived()._rows(); }
    /** \returns the number of columns. \sa row(), ColsAtCompileTime*/
    inline int cols() const { return derived()._cols(); }
    /** \returns the number of coefficients, which is \a rows()*cols().
      * \sa rows(), cols(), SizeAtCompileTime. */
    inline int size() const { return rows() * cols(); }
    /** \returns true if either the number of rows or the number of columns is equal to 1.
      * In other words, this function returns
      * \code rows()==1 || cols()==1 \endcode
      * \sa rows(), cols(), IsVectorAtCompileTime. */
    inline bool isVector() const { return rows()==1 || cols()==1; }


    /** Represents a constant matrix */
    typedef CwiseNullaryOp<ei_scalar_constant_op<Scalar>,Derived> ConstantReturnType;
    /** Represents a vector block of a matrix  */
    template<int Size> struct SubVectorReturnType
    {
      typedef Block<Derived, (ei_traits<Derived>::RowsAtCompileTime == 1 ? 1 : Size),
                             (ei_traits<Derived>::ColsAtCompileTime == 1 ? 1 : Size)> Type;
    };
    /** Represents a product scalar-matrix */
    typedef CwiseUnaryOp<ei_scalar_multiple_op<Scalar>, Derived> ScalarMultipleReturnType;
    /** */
    template<typename OtherDerived>
    struct ProductReturnType
    {
      typedef typename ei_meta_if<
            (Derived::Flags & OtherDerived::Flags & ArrayBit),
            CwiseBinaryOp<ei_scalar_product_op<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>,
            Product<Derived,OtherDerived>
          >::ret Type;
    };
    /** the return type of MatrixBase::conjugate() */
    typedef typename ei_meta_if<NumTraits<Scalar>::IsComplex,
                        CwiseUnaryOp<ei_scalar_conjugate_op<Scalar>, Derived>,
                        Derived&
                     >::ret ConjugateReturnType;
    /** the return type of MatrixBase::real() */
    typedef CwiseUnaryOp<ei_scalar_real_op<Scalar>, Derived> RealReturnType;
    /** the return type of MatrixBase::adjoint() */
    typedef Transpose<NestByValue<typename ei_unref<ConjugateReturnType>::type> >
            AdjointReturnType;
    typedef Matrix<typename NumTraits<typename ei_traits<Derived>::Scalar>::Real, ei_traits<Derived>::ColsAtCompileTime, 1> EigenvaluesReturnType;


    /** Copies \a other into *this. \returns a reference to *this. */
    template<typename OtherDerived>
    Derived& operator=(const MatrixBase<OtherDerived>& other);

    /** Copies \a other into *this without evaluating other. \returns a reference to *this. */
    template<typename OtherDerived>
    Derived& lazyAssign(const MatrixBase<OtherDerived>& other);

    /** Special case of the template operator=, in order to prevent the compiler
      * from generating a default operator= (issue hit with g++ 4.1)
      */
    inline Derived& operator=(const MatrixBase& other)
    {
      return this->operator=<Derived>(other);
    }

    /** Overloaded for optimal product evaluation */
    template<typename Derived1, typename Derived2>
    Derived& lazyAssign(const Product<Derived1,Derived2,CacheFriendlyProduct>& product);

    CommaInitializer operator<< (const Scalar& s);

    template<typename OtherDerived>
    CommaInitializer operator<< (const MatrixBase<OtherDerived>& other);

    const Scalar coeff(int row, int col) const;
    const Scalar operator()(int row, int col) const;

    Scalar& coeffRef(int row, int col);
    Scalar& operator()(int row, int col);

    const Scalar coeff(int index) const;
    const Scalar operator[](int index) const;

    Scalar& coeffRef(int index);
    Scalar& operator[](int index);

    template<int LoadMode>
    PacketScalar packetCoeff(int row, int col) const;
    template<int StoreMode>
    void writePacketCoeff(int row, int col, const PacketScalar& x);

    const Scalar x() const;
    const Scalar y() const;
    const Scalar z() const;
    const Scalar w() const;
    Scalar& x();
    Scalar& y();
    Scalar& z();
    Scalar& w();


    const CwiseUnaryOp<ei_scalar_opposite_op<typename ei_traits<Derived>::Scalar>,Derived> operator-() const;

    template<typename OtherDerived>
    const CwiseBinaryOp<ei_scalar_sum_op<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    operator+(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    const CwiseBinaryOp<ei_scalar_difference_op<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    operator-(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    Derived& operator+=(const MatrixBase<OtherDerived>& other);
    template<typename OtherDerived>
    Derived& operator-=(const MatrixBase<OtherDerived>& other);

    template<typename Lhs,typename Rhs>
    Derived& operator+=(const Flagged<Product<Lhs,Rhs,CacheFriendlyProduct>, 0, EvalBeforeNestingBit | EvalBeforeAssigningBit>& other);

    Derived& operator*=(const Scalar& other);
    Derived& operator/=(const Scalar& other);

    const ScalarMultipleReturnType operator*(const Scalar& scalar) const;
    const CwiseUnaryOp<ei_scalar_quotient1_op<typename ei_traits<Derived>::Scalar>, Derived>
    operator/(const Scalar& scalar) const;

    inline friend const CwiseUnaryOp<ei_scalar_multiple_op<typename ei_traits<Derived>::Scalar>, Derived>
    operator*(const Scalar& scalar, const MatrixBase& matrix)
    { return matrix*scalar; }


    template<typename OtherDerived>
    const typename ProductReturnType<OtherDerived>::Type
    operator*(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    Derived& operator*=(const MatrixBase<OtherDerived>& other);

    template<typename OtherDerived>
    typename OtherDerived::Eval inverseProduct(const MatrixBase<OtherDerived>& other) const;


    template<typename OtherDerived>
    Scalar dot(const MatrixBase<OtherDerived>& other) const;
    RealScalar norm2() const;
    RealScalar norm()  const;
    const ScalarMultipleReturnType normalized() const;

    Transpose<Derived> transpose();
    const Transpose<Derived> transpose() const;
    const AdjointReturnType adjoint() const;


    Block<Derived, 1, ei_traits<Derived>::ColsAtCompileTime> row(int i);
    const Block<Derived, 1, ei_traits<Derived>::ColsAtCompileTime> row(int i) const;

    Block<Derived, ei_traits<Derived>::RowsAtCompileTime, 1> col(int i);
    const Block<Derived, ei_traits<Derived>::RowsAtCompileTime, 1> col(int i) const;

    Minor<Derived> minor(int row, int col);
    const Minor<Derived> minor(int row, int col) const;

    Block<Derived> block(int startRow, int startCol, int blockRows, int blockCols);
    const Block<Derived>
    block(int startRow, int startCol, int blockRows, int blockCols) const;

    Block<Derived> block(int start, int size);
    const Block<Derived> block(int start, int size) const;

    Block<Derived> start(int size);
    const Block<Derived> start(int size) const;

    Block<Derived> end(int size);
    const Block<Derived> end(int size) const;

    Block<Derived> corner(CornerType type, int cRows, int cCols);
    const Block<Derived> corner(CornerType type, int cRows, int cCols) const;

    template<int BlockRows, int BlockCols>
    Block<Derived, BlockRows, BlockCols> block(int startRow, int startCol);
    template<int BlockRows, int BlockCols>
    const Block<Derived, BlockRows, BlockCols> block(int startRow, int startCol) const;

    template<int CRows, int CCols> Block<Derived, CRows, CCols> corner(CornerType type);
    template<int CRows, int CCols> const Block<Derived, CRows, CCols> corner(CornerType type) const;

    template<int Size>
    typename SubVectorReturnType<Size>::Type start(void);
    template<int Size>
    const typename SubVectorReturnType<Size>::Type start() const;

    template<int Size>
    typename SubVectorReturnType<Size>::Type end();
    template<int Size>
    const typename SubVectorReturnType<Size>::Type end() const;

    DiagonalCoeffs<Derived> diagonal();
    const DiagonalCoeffs<Derived> diagonal() const;

    template<unsigned int Mode> Part<Derived, Mode> part();
    template<unsigned int Mode> const Extract<Derived, Mode> extract() const;


    static const ConstantReturnType
    constant(int rows, int cols, const Scalar& value);
    static const ConstantReturnType
    constant(int size, const Scalar& value);
    static const ConstantReturnType
    constant(const Scalar& value);

    template<typename CustomNullaryOp>
    static const CwiseNullaryOp<CustomNullaryOp, Derived>
    create(int rows, int cols, const CustomNullaryOp& func);
    template<typename CustomNullaryOp>
    static const CwiseNullaryOp<CustomNullaryOp, Derived>
    create(int size, const CustomNullaryOp& func);
    template<typename CustomNullaryOp>
    static const CwiseNullaryOp<CustomNullaryOp, Derived>
    create(const CustomNullaryOp& func);

    static const ConstantReturnType zero(int rows, int cols);
    static const ConstantReturnType zero(int size);
    static const ConstantReturnType zero();
    static const ConstantReturnType ones(int rows, int cols);
    static const ConstantReturnType ones(int size);
    static const ConstantReturnType ones();
    static const CwiseNullaryOp<ei_scalar_identity_op<Scalar>,Derived> identity();
    static const CwiseNullaryOp<ei_scalar_identity_op<Scalar>,Derived> identity(int rows, int cols);

    const DiagonalMatrix<Derived> asDiagonal() const;

    Derived& setConstant(const Scalar& value);
    Derived& setZero();
    Derived& setOnes();
    Derived& setRandom();
    Derived& setIdentity();


    template<typename OtherDerived>
    bool isApprox(const MatrixBase<OtherDerived>& other,
                  RealScalar prec = precision<Scalar>()) const;
    bool isMuchSmallerThan(const RealScalar& other,
                           RealScalar prec = precision<Scalar>()) const;
    template<typename OtherDerived>
    bool isMuchSmallerThan(const MatrixBase<OtherDerived>& other,
                           RealScalar prec = precision<Scalar>()) const;

    bool isApproxToConstant(const Scalar& value, RealScalar prec = precision<Scalar>()) const;
    bool isZero(RealScalar prec = precision<Scalar>()) const;
    bool isOnes(RealScalar prec = precision<Scalar>()) const;
    bool isIdentity(RealScalar prec = precision<Scalar>()) const;
    bool isDiagonal(RealScalar prec = precision<Scalar>()) const;

    bool isUpper(RealScalar prec = precision<Scalar>()) const;
    bool isLower(RealScalar prec = precision<Scalar>()) const;

    template<typename OtherDerived>
    bool isOrtho(const MatrixBase<OtherDerived>& other,
                 RealScalar prec = precision<Scalar>()) const;
    bool isOrtho(RealScalar prec = precision<Scalar>()) const;

    template<typename OtherDerived>
    inline bool operator==(const MatrixBase<OtherDerived>& other) const
    { return derived().cwiseEqualTo(other.derived()).all(); }

    template<typename OtherDerived>
    inline bool operator!=(const MatrixBase<OtherDerived>& other) const
    { return derived().cwiseNotEqualTo(other.derived()).all(); }


    template<typename NewType>
    const CwiseUnaryOp<ei_scalar_cast_op<typename ei_traits<Derived>::Scalar, NewType>, Derived> cast() const;

    EIGEN_ALWAYS_INLINE const typename ei_eval<Derived>::type eval() const
    {
      return typename ei_eval<Derived>::type(derived());
    }

    template<typename OtherDerived>
    void swap(const MatrixBase<OtherDerived>& other);

    template<unsigned int Added>
    const Flagged<Derived, Added, 0> marked() const;
    const Flagged<Derived, 0, EvalBeforeNestingBit | EvalBeforeAssigningBit> lazy() const;

    /** \returns number of elements to skip to pass from one row (resp. column) to another
      * for a row-major (resp. column-major) matrix.
      * Combined with coeffRef() and the compile times flags, it allows a direct access to the data
      * of the underlying matrix.
      */
    inline int stride(void) const { return derived()._stride(); }

    inline const NestByValue<Derived> nestByValue() const;


    const ConjugateReturnType conjugate() const;
    const RealReturnType real() const;

    template<typename OtherDerived>
    const CwiseBinaryOp<ei_scalar_product_op<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseProduct(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    const CwiseBinaryOp<ei_scalar_quotient_op<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseQuotient(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    const CwiseBinaryOp<ei_scalar_min_op<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseMin(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    const CwiseBinaryOp<ei_scalar_max_op<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseMax(const MatrixBase<OtherDerived> &other) const;

    const CwiseUnaryOp<ei_scalar_abs_op<typename ei_traits<Derived>::Scalar>, Derived> cwiseAbs() const;
    const CwiseUnaryOp<ei_scalar_abs2_op<typename ei_traits<Derived>::Scalar>, Derived> cwiseAbs2() const;

    template<typename CustomUnaryOp>
    const CwiseUnaryOp<CustomUnaryOp, Derived> cwise(const CustomUnaryOp& func = CustomUnaryOp()) const;

    template<typename CustomBinaryOp, typename OtherDerived>
    const CwiseBinaryOp<CustomBinaryOp, Derived, OtherDerived>
    cwise(const MatrixBase<OtherDerived> &other, const CustomBinaryOp& func = CustomBinaryOp()) const;


    Scalar sum() const;
    Scalar trace() const;

    typename ei_traits<Derived>::Scalar minCoeff() const;
    typename ei_traits<Derived>::Scalar maxCoeff() const;

    typename ei_traits<Derived>::Scalar minCoeff(int* row, int* col = 0) const;
    typename ei_traits<Derived>::Scalar maxCoeff(int* row, int* col = 0) const;

    template<typename BinaryOp>
    typename ei_result_of<BinaryOp(typename ei_traits<Derived>::Scalar)>::type
    redux(const BinaryOp& func) const;

    template<typename Visitor>
    void visit(Visitor& func) const;


    inline const Derived& derived() const { return *static_cast<const Derived*>(this); }
    inline Derived& derived() { return *static_cast<Derived*>(this); }
    inline Derived& const_cast_derived() const
    { return *static_cast<Derived*>(const_cast<MatrixBase*>(this)); }


/////////// Array module ///////////

    const CwiseUnaryOp<ei_scalar_sqrt_op<typename ei_traits<Derived>::Scalar>, Derived> cwiseSqrt() const;
    const CwiseUnaryOp<ei_scalar_exp_op<typename ei_traits<Derived>::Scalar>, Derived> cwiseExp() const;
    const CwiseUnaryOp<ei_scalar_log_op<typename ei_traits<Derived>::Scalar>, Derived> cwiseLog() const;
    const CwiseUnaryOp<ei_scalar_cos_op<typename ei_traits<Derived>::Scalar>, Derived> cwiseCos() const;
    const CwiseUnaryOp<ei_scalar_sin_op<typename ei_traits<Derived>::Scalar>, Derived> cwiseSin() const;
    const CwiseUnaryOp<ei_scalar_pow_op<typename ei_traits<Derived>::Scalar>, Derived>
    cwisePow(const Scalar& exponent) const;
    const CwiseUnaryOp<ei_scalar_inverse_op<typename ei_traits<Derived>::Scalar>, Derived> cwiseInverse() const;

    template<typename OtherDerived>
    const CwiseBinaryOp<std::less<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseLessThan(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    const CwiseBinaryOp<std::less_equal<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseLessEqual(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    const CwiseBinaryOp<std::greater<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseGreaterThan(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    const CwiseBinaryOp<std::greater_equal<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseGreaterEqual(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    const CwiseBinaryOp<std::equal_to<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseEqualTo(const MatrixBase<OtherDerived> &other) const;

    template<typename OtherDerived>
    const CwiseBinaryOp<std::not_equal_to<typename ei_traits<Derived>::Scalar>, Derived, OtherDerived>
    cwiseNotEqualTo(const MatrixBase<OtherDerived> &other) const;

    bool all(void) const;
    bool any(void) const;

    template<typename BinaryOp>
    const PartialRedux<Vertical, BinaryOp, Derived>
    verticalRedux(const BinaryOp& func) const;

    template<typename BinaryOp>
    const PartialRedux<Horizontal, BinaryOp, Derived>
    horizontalRedux(const BinaryOp& func) const;

    static const CwiseNullaryOp<ei_scalar_random_op<Scalar>,Derived> random(int rows, int cols);
    static const CwiseNullaryOp<ei_scalar_random_op<Scalar>,Derived> random(int size);
    static const CwiseNullaryOp<ei_scalar_random_op<Scalar>,Derived> random();


/////////// LU module ///////////

    const Inverse<typename ei_eval<Derived>::type, true> inverse() const;
    const Inverse<typename ei_eval<Derived>::type, false> quickInverse() const;
    Scalar determinant() const;


/////////// QR module ///////////

    const QR<typename ei_eval<Derived>::type> qr() const;
    
    EigenvaluesReturnType eigenvalues() const;
    RealScalar matrixNorm() const;

};

#endif // EIGEN_MATRIXBASE_H