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finish to merge Array into Core:
- mv Array/* into Core/ - merge Functors.h files, and move Norms.h into Dot.h
This commit is contained in:
Gael Guennebaud
218
Eigen/src/Core/Reverse.h
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218
Eigen/src/Core/Reverse.h
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// This file is part of Eigen, a lightweight C++ template library
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// for linear algebra.
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//
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// Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com>
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// Copyright (C) 2009 Ricard Marxer <email@ricardmarxer.com>
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// Copyright (C) 2009-2010 Gael Guennebaud <g.gael@free.fr>
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//
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// Eigen is free software; you can redistribute it and/or
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// modify it under the terms of the GNU Lesser General Public
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// License as published by the Free Software Foundation; either
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// version 3 of the License, or (at your option) any later version.
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//
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// Alternatively, you can redistribute it and/or
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// modify it under the terms of the GNU General Public License as
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// published by the Free Software Foundation; either version 2 of
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// the License, or (at your option) any later version.
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//
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// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
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// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public
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// License and a copy of the GNU General Public License along with
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// Eigen. If not, see <http://www.gnu.org/licenses/>.
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#ifndef EIGEN_REVERSE_H
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#define EIGEN_REVERSE_H
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/** \class Reverse
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*
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* \brief Expression of the reverse of a vector or matrix
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*
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* \param MatrixType the type of the object of which we are taking the reverse
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*
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* This class represents an expression of the reverse of a vector.
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* It is the return type of MatrixBase::reverse() and VectorwiseOp::reverse()
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* and most of the time this is the only way it is used.
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*
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* \sa MatrixBase::reverse(), VectorwiseOp::reverse()
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*/
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template<typename MatrixType, int Direction>
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struct ei_traits<Reverse<MatrixType, Direction> >
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: ei_traits<MatrixType>
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{
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typedef typename MatrixType::Scalar Scalar;
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typedef typename ei_traits<MatrixType>::StorageKind StorageKind;
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typedef typename ei_traits<MatrixType>::XprKind XprKind;
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typedef typename ei_nested<MatrixType>::type MatrixTypeNested;
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typedef typename ei_unref<MatrixTypeNested>::type _MatrixTypeNested;
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enum {
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RowsAtCompileTime = MatrixType::RowsAtCompileTime,
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ColsAtCompileTime = MatrixType::ColsAtCompileTime,
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MaxRowsAtCompileTime = MatrixType::MaxRowsAtCompileTime,
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MaxColsAtCompileTime = MatrixType::MaxColsAtCompileTime,
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// let's enable LinearAccess only with vectorization because of the product overhead
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LinearAccess = ( (Direction==BothDirections) && (int(_MatrixTypeNested::Flags)&PacketAccessBit) )
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? LinearAccessBit : 0,
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Flags = int(_MatrixTypeNested::Flags) & (HereditaryBits | PacketAccessBit | LinearAccess),
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CoeffReadCost = _MatrixTypeNested::CoeffReadCost
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};
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};
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template<typename PacketScalar, bool ReversePacket> struct ei_reverse_packet_cond
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{
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static inline PacketScalar run(const PacketScalar& x) { return ei_preverse(x); }
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};
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template<typename PacketScalar> struct ei_reverse_packet_cond<PacketScalar,false>
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{
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static inline PacketScalar run(const PacketScalar& x) { return x; }
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};
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template<typename MatrixType, int Direction> class Reverse
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: public ei_dense_xpr_base< Reverse<MatrixType, Direction> >::type
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{
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public:
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typedef typename ei_dense_xpr_base<Reverse>::type Base;
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EIGEN_DENSE_PUBLIC_INTERFACE(Reverse)
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using Base::IsRowMajor;
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// next line is necessary because otherwise const version of operator()
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// is hidden by non-const version defined in this file
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using Base::operator();
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protected:
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enum {
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PacketSize = ei_packet_traits<Scalar>::size,
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IsColMajor = !IsRowMajor,
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ReverseRow = (Direction == Vertical) || (Direction == BothDirections),
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ReverseCol = (Direction == Horizontal) || (Direction == BothDirections),
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OffsetRow = ReverseRow && IsColMajor ? PacketSize : 1,
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OffsetCol = ReverseCol && IsRowMajor ? PacketSize : 1,
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ReversePacket = (Direction == BothDirections)
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|| ((Direction == Vertical) && IsColMajor)
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|| ((Direction == Horizontal) && IsRowMajor)
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};
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typedef ei_reverse_packet_cond<PacketScalar,ReversePacket> reverse_packet;
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public:
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inline Reverse(const MatrixType& matrix) : m_matrix(matrix) { }
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EIGEN_INHERIT_ASSIGNMENT_OPERATORS(Reverse)
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inline Index rows() const { return m_matrix.rows(); }
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inline Index cols() const { return m_matrix.cols(); }
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inline Scalar& operator()(Index row, Index col)
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{
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ei_assert(row >= 0 && row < rows() && col >= 0 && col < cols());
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return coeffRef(row, col);
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}
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inline Scalar& coeffRef(Index row, Index col)
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{
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return m_matrix.const_cast_derived().coeffRef(ReverseRow ? m_matrix.rows() - row - 1 : row,
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ReverseCol ? m_matrix.cols() - col - 1 : col);
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}
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inline const Scalar coeff(Index row, Index col) const
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{
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return m_matrix.coeff(ReverseRow ? m_matrix.rows() - row - 1 : row,
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ReverseCol ? m_matrix.cols() - col - 1 : col);
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}
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inline const Scalar coeff(Index index) const
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{
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return m_matrix.coeff(m_matrix.size() - index - 1);
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}
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inline Scalar& coeffRef(Index index)
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{
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return m_matrix.const_cast_derived().coeffRef(m_matrix.size() - index - 1);
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}
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inline Scalar& operator()(Index index)
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{
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ei_assert(index >= 0 && index < m_matrix.size());
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return coeffRef(index);
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}
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template<int LoadMode>
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inline const PacketScalar packet(Index row, Index col) const
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{
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return reverse_packet::run(m_matrix.template packet<LoadMode>(
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ReverseRow ? m_matrix.rows() - row - OffsetRow : row,
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ReverseCol ? m_matrix.cols() - col - OffsetCol : col));
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}
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template<int LoadMode>
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inline void writePacket(Index row, Index col, const PacketScalar& x)
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{
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m_matrix.const_cast_derived().template writePacket<LoadMode>(
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ReverseRow ? m_matrix.rows() - row - OffsetRow : row,
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ReverseCol ? m_matrix.cols() - col - OffsetCol : col,
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reverse_packet::run(x));
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}
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template<int LoadMode>
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inline const PacketScalar packet(Index index) const
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{
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return ei_preverse(m_matrix.template packet<LoadMode>( m_matrix.size() - index - PacketSize ));
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}
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template<int LoadMode>
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inline void writePacket(Index index, const PacketScalar& x)
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{
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m_matrix.const_cast_derived().template writePacket<LoadMode>(m_matrix.size() - index - PacketSize, ei_preverse(x));
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}
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protected:
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const typename MatrixType::Nested m_matrix;
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};
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/** \returns an expression of the reverse of *this.
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*
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* Example: \include MatrixBase_reverse.cpp
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* Output: \verbinclude MatrixBase_reverse.out
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*
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*/
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template<typename Derived>
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inline Reverse<Derived, BothDirections>
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DenseBase<Derived>::reverse()
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{
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return derived();
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}
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/** This is the const version of reverse(). */
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template<typename Derived>
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inline const Reverse<Derived, BothDirections>
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DenseBase<Derived>::reverse() const
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{
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return derived();
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}
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/** This is the "in place" version of reverse: it reverses \c *this.
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*
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* In most cases it is probably better to simply use the reversed expression
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* of a matrix. However, when reversing the matrix data itself is really needed,
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* then this "in-place" version is probably the right choice because it provides
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* the following additional features:
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* - less error prone: doing the same operation with .reverse() requires special care:
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* \code m = m.reverse().eval(); \endcode
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* - no temporary object is created (currently there is one created but could be avoided using swap)
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* - it allows future optimizations (cache friendliness, etc.)
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*
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* \sa reverse() */
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template<typename Derived>
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inline void DenseBase<Derived>::reverseInPlace()
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{
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derived() = derived().reverse().eval();
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}
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#endif // EIGEN_REVERSE_H
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