// This file is part of Eigen, a lightweight C++ template library // for linear algebra. // // Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com> // Copyright (C) 2009-2014 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/.
template<typename MatrixType, typename StorageKind> class TransposeImpl;
/** \class Transpose * \ingroup Core_Module * * \brief Expression of the transpose of a matrix * * \tparam MatrixType the type of the object of which we are taking the transpose * * This class represents an expression of the transpose of a matrix. * It is the return type of MatrixBase::transpose() and MatrixBase::adjoint() * and most of the time this is the only way it is used. * * \sa MatrixBase::transpose(), MatrixBase::adjoint()
*/ template<typename MatrixType> class Transpose
: public TransposeImpl<MatrixType,typename internal::traits<MatrixType>::StorageKind>
{ public:
// FIXME: shall we keep the const version of coeffRef?
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar& coeffRef(Index rowId, Index colId) const
{ return derived().nestedExpression().coeffRef(colId, rowId);
}
/** \returns an expression of the transpose of *this. * * Example: \include MatrixBase_transpose.cpp * Output: \verbinclude MatrixBase_transpose.out * * \warning If you want to replace a matrix by its own transpose, do \b NOT do this: * \code * m = m.transpose(); // bug!!! caused by aliasing effect * \endcode * Instead, use the transposeInPlace() method: * \code * m.transposeInPlace(); * \endcode * which gives Eigen good opportunities for optimization, or alternatively you can also do: * \code * m = m.transpose().eval(); * \endcode *
* \sa transposeInPlace(), adjoint() */ template<typename Derived>
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
Transpose<Derived>
DenseBase<Derived>::transpose()
{ return TransposeReturnType(derived());
}
/** This is the const version of transpose(). * * Make sure you read the warning for transpose() ! *
* \sa transposeInPlace(), adjoint() */ template<typename Derived>
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE typename DenseBase<Derived>::ConstTransposeReturnType
DenseBase<Derived>::transpose() const
{ return ConstTransposeReturnType(derived());
}
/** \returns an expression of the adjoint (i.e. conjugate transpose) of *this. * * Example: \include MatrixBase_adjoint.cpp * Output: \verbinclude MatrixBase_adjoint.out * * \warning If you want to replace a matrix by its own adjoint, do \b NOT do this: * \code * m = m.adjoint(); // bug!!! caused by aliasing effect * \endcode * Instead, use the adjointInPlace() method: * \code * m.adjointInPlace(); * \endcode * which gives Eigen good opportunities for optimization, or alternatively you can also do: * \code * m = m.adjoint().eval(); * \endcode *
* \sa adjointInPlace(), transpose(), conjugate(), class Transpose, class internal::scalar_conjugate_op */ template<typename Derived>
EIGEN_DEVICE_FUNC inlineconsttypename MatrixBase<Derived>::AdjointReturnType
MatrixBase<Derived>::adjoint() const
{ return AdjointReturnType(this->transpose());
}
/*************************************************************************** * "in place" transpose implementation
***************************************************************************/
template<typename MatrixType> struct inplace_transpose_selector<MatrixType,true,true> { // PacketSize x PacketSize staticvoid run(MatrixType& m) { typedeftypename MatrixType::Scalar Scalar; typedeftypename internal::packet_traits<typename MatrixType::Scalar>::type Packet; const Index PacketSize = internal::packet_traits<Scalar>::size; const Index Alignment = internal::evaluator<MatrixType>::Alignment;
PacketBlock<Packet> A; for (Index i=0; i<PacketSize; ++i)
A.packet[i] = m.template packetByOuterInner<Alignment>(i,0);
internal::ptranspose(A); for (Index i=0; i<PacketSize; ++i)
m.template writePacket<Alignment>(m.rowIndexByOuterInner(i,0), m.colIndexByOuterInner(i,0), A.packet[i]);
}
};
template <typename MatrixType, Index Alignment> void BlockedInPlaceTranspose(MatrixType& m) { typedeftypename MatrixType::Scalar Scalar; typedeftypename internal::packet_traits<typename MatrixType::Scalar>::type Packet; const Index PacketSize = internal::packet_traits<Scalar>::size;
eigen_assert(m.rows() == m.cols()); int row_start = 0; for (; row_start + PacketSize <= m.rows(); row_start += PacketSize) { for (int col_start = row_start; col_start + PacketSize <= m.cols(); col_start += PacketSize) {
PacketBlock<Packet> A; if (row_start == col_start) { for (Index i=0; i<PacketSize; ++i)
A.packet[i] = m.template packetByOuterInner<Alignment>(row_start + i,col_start);
internal::ptranspose(A); for (Index i=0; i<PacketSize; ++i)
m.template writePacket<Alignment>(m.rowIndexByOuterInner(row_start + i, col_start), m.colIndexByOuterInner(row_start + i,col_start), A.packet[i]);
} else {
PacketBlock<Packet> B; for (Index i=0; i<PacketSize; ++i) {
A.packet[i] = m.template packetByOuterInner<Alignment>(row_start + i,col_start);
B.packet[i] = m.template packetByOuterInner<Alignment>(col_start + i, row_start);
}
internal::ptranspose(A);
internal::ptranspose(B); for (Index i=0; i<PacketSize; ++i) {
m.template writePacket<Alignment>(m.rowIndexByOuterInner(row_start + i, col_start), m.colIndexByOuterInner(row_start + i,col_start), B.packet[i]);
m.template writePacket<Alignment>(m.rowIndexByOuterInner(col_start + i, row_start), m.colIndexByOuterInner(col_start + i,row_start), A.packet[i]);
}
}
}
} for (Index row = row_start; row < m.rows(); ++row) {
m.matrix().row(row).head(row).swap(
m.matrix().col(row).head(row).transpose());
}
}
template<typename MatrixType,bool MatchPacketSize> struct inplace_transpose_selector<MatrixType,false,MatchPacketSize> { // non square or dynamic matrix staticvoid run(MatrixType& m) { typedeftypename MatrixType::Scalar Scalar; if (m.rows() == m.cols()) { const Index PacketSize = internal::packet_traits<Scalar>::size; if (!NumTraits<Scalar>::IsComplex && m.rows() >= PacketSize) { if ((m.rows() % PacketSize) == 0)
BlockedInPlaceTranspose<MatrixType,internal::evaluator<MatrixType>::Alignment>(m); else
BlockedInPlaceTranspose<MatrixType,Unaligned>(m);
} else {
m.matrix().template triangularView<StrictlyUpper>().swap(m.matrix().transpose().template triangularView<StrictlyUpper>());
}
} else {
m = m.transpose().eval();
}
}
};
} // end namespace internal
/** This is the "in place" version of transpose(): it replaces \c *this by its own transpose. * Thus, doing * \code * m.transposeInPlace(); * \endcode * has the same effect on m as doing * \code * m = m.transpose().eval(); * \endcode * and is faster and also safer because in the latter line of code, forgetting the eval() results * in a bug caused by \ref TopicAliasing "aliasing". * * Notice however that this method is only useful if you want to replace a matrix by its own transpose. * If you just need the transpose of a matrix, use transpose(). * * \note if the matrix is not square, then \c *this must be a resizable matrix. * This excludes (non-square) fixed-size matrices, block-expressions and maps. *
* \sa transpose(), adjoint(), adjointInPlace() */ template<typename Derived>
EIGEN_DEVICE_FUNC inlinevoid DenseBase<Derived>::transposeInPlace()
{
eigen_assert((rows() == cols() || (RowsAtCompileTime == Dynamic && ColsAtCompileTime == Dynamic))
&& "transposeInPlace() called on a non-square non-resizable matrix");
internal::inplace_transpose_selector<Derived>::run(derived());
}
/*************************************************************************** * "in place" adjoint implementation
***************************************************************************/
/** This is the "in place" version of adjoint(): it replaces \c *this by its own transpose. * Thus, doing * \code * m.adjointInPlace(); * \endcode * has the same effect on m as doing * \code * m = m.adjoint().eval(); * \endcode * and is faster and also safer because in the latter line of code, forgetting the eval() results * in a bug caused by aliasing. * * Notice however that this method is only useful if you want to replace a matrix by its own adjoint. * If you just need the adjoint of a matrix, use adjoint(). * * \note if the matrix is not square, then \c *this must be a resizable matrix. * This excludes (non-square) fixed-size matrices, block-expressions and maps. *
* \sa transpose(), adjoint(), transposeInPlace() */ template<typename Derived>
EIGEN_DEVICE_FUNC inlinevoid MatrixBase<Derived>::adjointInPlace()
{
derived() = adjoint().eval();
}
#ifndef EIGEN_NO_DEBUG
// The following is to detect aliasing problems in most common cases.
// the following selector, checkTransposeAliasing_impl, based on MightHaveTransposeAliasing, // is because when the condition controlling the assert is known at compile time, ICC emits a warning. // This is actually a good warning: in expressions that don't have any transposing, the condition is // known at compile time to be false, and using that, we can avoid generating the code of the assert again // and again for all these expressions that don't need it.
template<typename Derived, typename OtherDerived, bool MightHaveTransposeAliasing
= check_transpose_aliasing_compile_time_selector
<blas_traits<Derived>::IsTransposed,OtherDerived>::ret
> struct checkTransposeAliasing_impl
{ staticvoid run(const Derived& dst, const OtherDerived& other)
{
eigen_assert((!check_transpose_aliasing_run_time_selector
<typename Derived::Scalar,blas_traits<Derived>::IsTransposed,OtherDerived>
::run(extract_data(dst), other))
&& "aliasing detected during transposition, use transposeInPlace() " "or evaluate the rhs into a temporary using .eval()");
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