text: // This file is part of Eigen, a lightweight C++ template library
  // for linear algebra.
  //
  // Copyright (C) 2009 Gael Guennebaud <gael.guennebaud@inria.fr>
  //
  // This Source Code Form is subject to the terms of the Mozilla
  // Public License v. 2.0. If a copy of the MPL was not distributed
  // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
  
  #ifndef EIGEN_ARRAYBASE_H
  #define EIGEN_ARRAYBASE_H
  
  namespace Eigen { 
  
  template<typename ExpressionType> class MatrixWrapper;
  
  /** \class ArrayBase
    * \ingroup Core_Module
    *
    * \brief Base class for all 1D and 2D array, and related expressions
    *
    * An array is similar to a dense vector or matrix. While matrices are mathematical
    * objects with well defined linear algebra operators, an array is just a collection
    * of scalar values arranged in a one or two dimensionnal fashion. As the main consequence,
    * all operations applied to an array are performed coefficient wise. Furthermore,
    * arrays support scalar math functions of the c++ standard library (e.g., std::sin(x)), and convenient
    * constructors allowing to easily write generic code working for both scalar values
    * and arrays.
    *
    * This class is the base that is inherited by all array expression types.
    *
    * \tparam Derived is the derived type, e.g., an array or an expression type.
    *
    * This class can be extended with the help of the plugin mechanism described on the page
    * \ref TopicCustomizingEigen by defining the preprocessor symbol \c EIGEN_ARRAYBASE_PLUGIN.
    *
    * \sa class MatrixBase, \ref TopicClassHierarchy
    */
  template<typename Derived> class ArrayBase
    : public DenseBase<Derived>
  {
    public:
  #ifndef EIGEN_PARSED_BY_DOXYGEN
      /** The base class for a given storage type. */
      typedef ArrayBase StorageBaseType;
  
      typedef ArrayBase Eigen_BaseClassForSpecializationOfGlobalMathFuncImpl;
  
      using internal::special_scalar_op_base<Derived,typename internal::traits<Derived>::Scalar,
                  typename NumTraits<typename internal::traits<Derived>::Scalar>::Real>::operator*;
  
      typedef typename internal::traits<Derived>::StorageKind StorageKind;
      typedef typename internal::traits<Derived>::Index Index;
      typedef typename internal::traits<Derived>::Scalar Scalar;
      typedef typename internal::packet_traits<Scalar>::type PacketScalar;
      typedef typename NumTraits<Scalar>::Real RealScalar;
  
      typedef DenseBase<Derived> Base;
      using Base::RowsAtCompileTime;
      using Base::ColsAtCompileTime;
      using Base::SizeAtCompileTime;
      using Base::MaxRowsAtCompileTime;
      using Base::MaxColsAtCompileTime;
      using Base::MaxSizeAtCompileTime;
      using Base::IsVectorAtCompileTime;
      using Base::Flags;
      using Base::CoeffReadCost;
  
      using Base::derived;
      using Base::const_cast_derived;
      using Base::rows;
      using Base::cols;
      using Base::size;
      using Base::coeff;
      using Base::coeffRef;
      using Base::lazyAssign;
      using Base::operator=;
      using Base::operator+=;
      using Base::operator-=;
      using Base::operator*=;
      using Base::operator/=;
  
      typedef typename Base::CoeffReturnType CoeffReturnType;
  
  #endif // not EIGEN_PARSED_BY_DOXYGEN
  
  #ifndef EIGEN_PARSED_BY_DOXYGEN
      /** \internal the plain matrix type corresponding to this expression. Note that is not necessarily
        * exactly the return type of eval(): in the case of plain matrices, the return type of eval() is a const
        * reference to a matrix, not a matrix! It is however guaranteed that the return type of eval() is either
        * PlainObject or const PlainObject&.
        */
      typedef Array<typename internal::traits<Derived>::Scalar,
                  internal::traits<Derived>::RowsAtCompileTime,
                  internal::traits<Derived>::ColsAtCompileTime,
                  AutoAlign | (internal::traits<Derived>::Flags&RowMajorBit ? RowMajor : ColMajor),
                  internal::traits<Derived>::MaxRowsAtCompileTime,
                  internal::traits<Derived>::MaxColsAtCompileTime
            > PlainObject;
  
  
      /** \internal Represents a matrix with all coefficients equal to one another*/
      typedef CwiseNullaryOp<internal::scalar_constant_op<Scalar>,Derived> ConstantReturnType;
  #endif // not EIGEN_PARSED_BY_DOXYGEN
  
  #define EIGEN_CURRENT_STORAGE_BASE_CLASS Eigen::ArrayBase
  #   include "../plugins/CommonCwiseUnaryOps.h"
  #   include "../plugins/MatrixCwiseUnaryOps.h"
  #   include "../plugins/ArrayCwiseUnaryOps.h"
  #   include "../plugins/CommonCwiseBinaryOps.h"
  #   include "../plugins/MatrixCwiseBinaryOps.h"
  #   include "../plugins/ArrayCwiseBinaryOps.h"
  #   ifdef EIGEN_ARRAYBASE_PLUGIN
  #     include EIGEN_ARRAYBASE_PLUGIN
  #   endif
  #undef EIGEN_CURRENT_STORAGE_BASE_CLASS
  
      /** Special case of the template operator=, in order to prevent the compiler
        * from generating a default operator= (issue hit with g++ 4.1)
        */
      Derived& operator=(const ArrayBase& other)
      {
        return internal::assign_selector<Derived,Derived>::run(derived(), other.derived());
      }
  
      Derived& operator+=(const Scalar& scalar)
      { return *this = derived() + scalar; }
      Derived& operator-=(const Scalar& scalar)
      { return *this = derived() - scalar; }
  
      template<typename OtherDerived>
      Derived& operator+=(const ArrayBase<OtherDerived>& other);
      template<typename OtherDerived>
      Derived& operator-=(const ArrayBase<OtherDerived>& other);
  
      template<typename OtherDerived>
      Derived& operator*=(const ArrayBase<OtherDerived>& other);
  
      template<typename OtherDerived>
      Derived& operator/=(const ArrayBase<OtherDerived>& other);
  
    public:
      ArrayBase<Derived>& array() { return *this; }
      const ArrayBase<Derived>& array() const { return *this; }
  
      /** \returns an \link Eigen::MatrixBase Matrix \endlink expression of this array
        * \sa MatrixBase::array() */
      MatrixWrapper<Derived> matrix() { return derived(); }
      const MatrixWrapper<const Derived> matrix() const { return derived(); }
  
  //     template<typename Dest>
  //     inline void evalTo(Dest& dst) const { dst = matrix(); }
  
    protected:
      ArrayBase() : Base() {}
  
    private:
      explicit ArrayBase(Index);
      ArrayBase(Index,Index);
      template<typename OtherDerived> explicit ArrayBase(const ArrayBase<OtherDerived>&);
    protected:
      // mixing arrays and matrices is not legal
      template<typename OtherDerived> Derived& operator+=(const MatrixBase<OtherDerived>& )
      {EIGEN_STATIC_ASSERT(std::ptrdiff_t(sizeof(typename OtherDerived::Scalar))==-1,YOU_CANNOT_MIX_ARRAYS_AND_MATRICES); return *this;}
      // mixing arrays and matrices is not legal
      template<typename OtherDerived> Derived& operator-=(const MatrixBase<OtherDerived>& )
      {EIGEN_STATIC_ASSERT(std::ptrdiff_t(sizeof(typename OtherDerived::Scalar))==-1,YOU_CANNOT_MIX_ARRAYS_AND_MATRICES); return *this;}
  };
  
  /** replaces \c *this by \c *this - \a other.
    *
    * \returns a reference to \c *this
    */
  template<typename Derived>
  template<typename OtherDerived>
  EIGEN_STRONG_INLINE Derived &
  ArrayBase<Derived>::operator-=(const ArrayBase<OtherDerived> &other)
  {
    SelfCwiseBinaryOp<internal::scalar_difference_op<Scalar>, Derived, OtherDerived> tmp(derived());
    tmp = other.derived();
    return derived();
  }
  
  /** replaces \c *this by \c *this + \a other.
    *
    * \returns a reference to \c *this
    */
  template<typename Derived>
  template<typename OtherDerived>
  EIGEN_STRONG_INLINE Derived &
  ArrayBase<Derived>::operator+=(const ArrayBase<OtherDerived>& other)
  {
    SelfCwiseBinaryOp<internal::scalar_sum_op<Scalar>, Derived, OtherDerived> tmp(derived());
    tmp = other.derived();
    return derived();
  }
  
  /** replaces \c *this by \c *this * \a other coefficient wise.
    *
    * \returns a reference to \c *this
    */
  template<typename Derived>
  template<typename OtherDerived>
  EIGEN_STRONG_INLINE Derived &
  ArrayBase<Derived>::operator*=(const ArrayBase<OtherDerived>& other)
  {
    SelfCwiseBinaryOp<internal::scalar_product_op<Scalar>, Derived, OtherDerived> tmp(derived());
    tmp = other.derived();
    return derived();
  }
  
  /** replaces \c *this by \c *this / \a other coefficient wise.
    *
    * \returns a reference to \c *this
    */
  template<typename Derived>
  template<typename OtherDerived>
  EIGEN_STRONG_INLINE Derived &
  ArrayBase<Derived>::operator/=(const ArrayBase<OtherDerived>& other)
  {
    SelfCwiseBinaryOp<internal::scalar_quotient_op<Scalar>, Derived, OtherDerived> tmp(derived());
    tmp = other.derived();
    return derived();
  }
  
  } // end namespace Eigen
  
  #endif // EIGEN_ARRAYBASE_H
  