Home | History | Annotate | Download | only in Core
      1 // This file is part of Eigen, a lightweight C++ template library
      2 // for linear algebra.
      3 //
      4 // Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud (at) inria.fr>
      5 //
      6 // This Source Code Form is subject to the terms of the Mozilla
      7 // Public License v. 2.0. If a copy of the MPL was not distributed
      8 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
      9 
     10 #ifndef EIGEN_CWISE_UNARY_VIEW_H
     11 #define EIGEN_CWISE_UNARY_VIEW_H
     12 
     13 namespace Eigen {
     14 
     15 namespace internal {
     16 template<typename ViewOp, typename MatrixType>
     17 struct traits<CwiseUnaryView<ViewOp, MatrixType> >
     18  : traits<MatrixType>
     19 {
     20   typedef typename result_of<
     21                      ViewOp(const typename traits<MatrixType>::Scalar&)
     22                    >::type Scalar;
     23   typedef typename MatrixType::Nested MatrixTypeNested;
     24   typedef typename remove_all<MatrixTypeNested>::type _MatrixTypeNested;
     25   enum {
     26     FlagsLvalueBit = is_lvalue<MatrixType>::value ? LvalueBit : 0,
     27     Flags = traits<_MatrixTypeNested>::Flags & (RowMajorBit | FlagsLvalueBit | DirectAccessBit), // FIXME DirectAccessBit should not be handled by expressions
     28     MatrixTypeInnerStride =  inner_stride_at_compile_time<MatrixType>::ret,
     29     // need to cast the sizeof's from size_t to int explicitly, otherwise:
     30     // "error: no integral type can represent all of the enumerator values
     31     InnerStrideAtCompileTime = MatrixTypeInnerStride == Dynamic
     32                              ? int(Dynamic)
     33                              : int(MatrixTypeInnerStride) * int(sizeof(typename traits<MatrixType>::Scalar) / sizeof(Scalar)),
     34     OuterStrideAtCompileTime = outer_stride_at_compile_time<MatrixType>::ret == Dynamic
     35                              ? int(Dynamic)
     36                              : outer_stride_at_compile_time<MatrixType>::ret * int(sizeof(typename traits<MatrixType>::Scalar) / sizeof(Scalar))
     37   };
     38 };
     39 }
     40 
     41 template<typename ViewOp, typename MatrixType, typename StorageKind>
     42 class CwiseUnaryViewImpl;
     43 
     44 /** \class CwiseUnaryView
     45   * \ingroup Core_Module
     46   *
     47   * \brief Generic lvalue expression of a coefficient-wise unary operator of a matrix or a vector
     48   *
     49   * \tparam ViewOp template functor implementing the view
     50   * \tparam MatrixType the type of the matrix we are applying the unary operator
     51   *
     52   * This class represents a lvalue expression of a generic unary view operator of a matrix or a vector.
     53   * It is the return type of real() and imag(), and most of the time this is the only way it is used.
     54   *
     55   * \sa MatrixBase::unaryViewExpr(const CustomUnaryOp &) const, class CwiseUnaryOp
     56   */
     57 template<typename ViewOp, typename MatrixType>
     58 class CwiseUnaryView : public CwiseUnaryViewImpl<ViewOp, MatrixType, typename internal::traits<MatrixType>::StorageKind>
     59 {
     60   public:
     61 
     62     typedef typename CwiseUnaryViewImpl<ViewOp, MatrixType,typename internal::traits<MatrixType>::StorageKind>::Base Base;
     63     EIGEN_GENERIC_PUBLIC_INTERFACE(CwiseUnaryView)
     64     typedef typename internal::ref_selector<MatrixType>::non_const_type MatrixTypeNested;
     65     typedef typename internal::remove_all<MatrixType>::type NestedExpression;
     66 
     67     explicit inline CwiseUnaryView(MatrixType& mat, const ViewOp& func = ViewOp())
     68       : m_matrix(mat), m_functor(func) {}
     69 
     70     EIGEN_INHERIT_ASSIGNMENT_OPERATORS(CwiseUnaryView)
     71 
     72     EIGEN_STRONG_INLINE Index rows() const { return m_matrix.rows(); }
     73     EIGEN_STRONG_INLINE Index cols() const { return m_matrix.cols(); }
     74 
     75     /** \returns the functor representing unary operation */
     76     const ViewOp& functor() const { return m_functor; }
     77 
     78     /** \returns the nested expression */
     79     const typename internal::remove_all<MatrixTypeNested>::type&
     80     nestedExpression() const { return m_matrix; }
     81 
     82     /** \returns the nested expression */
     83     typename internal::remove_reference<MatrixTypeNested>::type&
     84     nestedExpression() { return m_matrix.const_cast_derived(); }
     85 
     86   protected:
     87     MatrixTypeNested m_matrix;
     88     ViewOp m_functor;
     89 };
     90 
     91 // Generic API dispatcher
     92 template<typename ViewOp, typename XprType, typename StorageKind>
     93 class CwiseUnaryViewImpl
     94   : public internal::generic_xpr_base<CwiseUnaryView<ViewOp, XprType> >::type
     95 {
     96 public:
     97   typedef typename internal::generic_xpr_base<CwiseUnaryView<ViewOp, XprType> >::type Base;
     98 };
     99 
    100 template<typename ViewOp, typename MatrixType>
    101 class CwiseUnaryViewImpl<ViewOp,MatrixType,Dense>
    102   : public internal::dense_xpr_base< CwiseUnaryView<ViewOp, MatrixType> >::type
    103 {
    104   public:
    105 
    106     typedef CwiseUnaryView<ViewOp, MatrixType> Derived;
    107     typedef typename internal::dense_xpr_base< CwiseUnaryView<ViewOp, MatrixType> >::type Base;
    108 
    109     EIGEN_DENSE_PUBLIC_INTERFACE(Derived)
    110     EIGEN_INHERIT_ASSIGNMENT_OPERATORS(CwiseUnaryViewImpl)
    111 
    112     EIGEN_DEVICE_FUNC inline Scalar* data() { return &(this->coeffRef(0)); }
    113     EIGEN_DEVICE_FUNC inline const Scalar* data() const { return &(this->coeff(0)); }
    114 
    115     EIGEN_DEVICE_FUNC inline Index innerStride() const
    116     {
    117       return derived().nestedExpression().innerStride() * sizeof(typename internal::traits<MatrixType>::Scalar) / sizeof(Scalar);
    118     }
    119 
    120     EIGEN_DEVICE_FUNC inline Index outerStride() const
    121     {
    122       return derived().nestedExpression().outerStride() * sizeof(typename internal::traits<MatrixType>::Scalar) / sizeof(Scalar);
    123     }
    124 };
    125 
    126 } // end namespace Eigen
    127 
    128 #endif // EIGEN_CWISE_UNARY_VIEW_H
    129