1 // This file is part of Eigen, a lightweight C++ template library 2 // for linear algebra. 3 // 4 // Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1 (at) gmail.com> 5 // Copyright (C) 2009-2014 Gael Guennebaud <gael.guennebaud (at) inria.fr> 6 // 7 // This Source Code Form is subject to the terms of the Mozilla 8 // Public License v. 2.0. If a copy of the MPL was not distributed 9 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/. 10 11 #ifndef EIGEN_TRANSPOSE_H 12 #define EIGEN_TRANSPOSE_H 13 14 namespace Eigen { 15 16 namespace internal { 17 template<typename MatrixType> 18 struct traits<Transpose<MatrixType> > : public traits<MatrixType> 19 { 20 typedef typename ref_selector<MatrixType>::type MatrixTypeNested; 21 typedef typename remove_reference<MatrixTypeNested>::type MatrixTypeNestedPlain; 22 enum { 23 RowsAtCompileTime = MatrixType::ColsAtCompileTime, 24 ColsAtCompileTime = MatrixType::RowsAtCompileTime, 25 MaxRowsAtCompileTime = MatrixType::MaxColsAtCompileTime, 26 MaxColsAtCompileTime = MatrixType::MaxRowsAtCompileTime, 27 FlagsLvalueBit = is_lvalue<MatrixType>::value ? LvalueBit : 0, 28 Flags0 = traits<MatrixTypeNestedPlain>::Flags & ~(LvalueBit | NestByRefBit), 29 Flags1 = Flags0 | FlagsLvalueBit, 30 Flags = Flags1 ^ RowMajorBit, 31 InnerStrideAtCompileTime = inner_stride_at_compile_time<MatrixType>::ret, 32 OuterStrideAtCompileTime = outer_stride_at_compile_time<MatrixType>::ret 33 }; 34 }; 35 } 36 37 template<typename MatrixType, typename StorageKind> class TransposeImpl; 38 39 /** \class Transpose 40 * \ingroup Core_Module 41 * 42 * \brief Expression of the transpose of a matrix 43 * 44 * \tparam MatrixType the type of the object of which we are taking the transpose 45 * 46 * This class represents an expression of the transpose of a matrix. 47 * It is the return type of MatrixBase::transpose() and MatrixBase::adjoint() 48 * and most of the time this is the only way it is used. 49 * 50 * \sa MatrixBase::transpose(), MatrixBase::adjoint() 51 */ 52 template<typename MatrixType> class Transpose 53 : public TransposeImpl<MatrixType,typename internal::traits<MatrixType>::StorageKind> 54 { 55 public: 56 57 typedef typename internal::ref_selector<MatrixType>::non_const_type MatrixTypeNested; 58 59 typedef typename TransposeImpl<MatrixType,typename internal::traits<MatrixType>::StorageKind>::Base Base; 60 EIGEN_GENERIC_PUBLIC_INTERFACE(Transpose) 61 typedef typename internal::remove_all<MatrixType>::type NestedExpression; 62 63 EIGEN_DEVICE_FUNC 64 explicit inline Transpose(MatrixType& matrix) : m_matrix(matrix) {} 65 66 EIGEN_INHERIT_ASSIGNMENT_OPERATORS(Transpose) 67 68 EIGEN_DEVICE_FUNC inline Index rows() const { return m_matrix.cols(); } 69 EIGEN_DEVICE_FUNC inline Index cols() const { return m_matrix.rows(); } 70 71 /** \returns the nested expression */ 72 EIGEN_DEVICE_FUNC 73 const typename internal::remove_all<MatrixTypeNested>::type& 74 nestedExpression() const { return m_matrix; } 75 76 /** \returns the nested expression */ 77 EIGEN_DEVICE_FUNC 78 typename internal::remove_reference<MatrixTypeNested>::type& 79 nestedExpression() { return m_matrix; } 80 81 /** \internal */ 82 void resize(Index nrows, Index ncols) { 83 m_matrix.resize(ncols,nrows); 84 } 85 86 protected: 87 typename internal::ref_selector<MatrixType>::non_const_type m_matrix; 88 }; 89 90 namespace internal { 91 92 template<typename MatrixType, bool HasDirectAccess = has_direct_access<MatrixType>::ret> 93 struct TransposeImpl_base 94 { 95 typedef typename dense_xpr_base<Transpose<MatrixType> >::type type; 96 }; 97 98 template<typename MatrixType> 99 struct TransposeImpl_base<MatrixType, false> 100 { 101 typedef typename dense_xpr_base<Transpose<MatrixType> >::type type; 102 }; 103 104 } // end namespace internal 105 106 // Generic API dispatcher 107 template<typename XprType, typename StorageKind> 108 class TransposeImpl 109 : public internal::generic_xpr_base<Transpose<XprType> >::type 110 { 111 public: 112 typedef typename internal::generic_xpr_base<Transpose<XprType> >::type Base; 113 }; 114 115 template<typename MatrixType> class TransposeImpl<MatrixType,Dense> 116 : public internal::TransposeImpl_base<MatrixType>::type 117 { 118 public: 119 120 typedef typename internal::TransposeImpl_base<MatrixType>::type Base; 121 using Base::coeffRef; 122 EIGEN_DENSE_PUBLIC_INTERFACE(Transpose<MatrixType>) 123 EIGEN_INHERIT_ASSIGNMENT_OPERATORS(TransposeImpl) 124 125 EIGEN_DEVICE_FUNC inline Index innerStride() const { return derived().nestedExpression().innerStride(); } 126 EIGEN_DEVICE_FUNC inline Index outerStride() const { return derived().nestedExpression().outerStride(); } 127 128 typedef typename internal::conditional< 129 internal::is_lvalue<MatrixType>::value, 130 Scalar, 131 const Scalar 132 >::type ScalarWithConstIfNotLvalue; 133 134 EIGEN_DEVICE_FUNC inline ScalarWithConstIfNotLvalue* data() { return derived().nestedExpression().data(); } 135 EIGEN_DEVICE_FUNC inline const Scalar* data() const { return derived().nestedExpression().data(); } 136 137 // FIXME: shall we keep the const version of coeffRef? 138 EIGEN_DEVICE_FUNC 139 inline const Scalar& coeffRef(Index rowId, Index colId) const 140 { 141 return derived().nestedExpression().coeffRef(colId, rowId); 142 } 143 144 EIGEN_DEVICE_FUNC 145 inline const Scalar& coeffRef(Index index) const 146 { 147 return derived().nestedExpression().coeffRef(index); 148 } 149 }; 150 151 /** \returns an expression of the transpose of *this. 152 * 153 * Example: \include MatrixBase_transpose.cpp 154 * Output: \verbinclude MatrixBase_transpose.out 155 * 156 * \warning If you want to replace a matrix by its own transpose, do \b NOT do this: 157 * \code 158 * m = m.transpose(); // bug!!! caused by aliasing effect 159 * \endcode 160 * Instead, use the transposeInPlace() method: 161 * \code 162 * m.transposeInPlace(); 163 * \endcode 164 * which gives Eigen good opportunities for optimization, or alternatively you can also do: 165 * \code 166 * m = m.transpose().eval(); 167 * \endcode 168 * 169 * \sa transposeInPlace(), adjoint() */ 170 template<typename Derived> 171 inline Transpose<Derived> 172 DenseBase<Derived>::transpose() 173 { 174 return TransposeReturnType(derived()); 175 } 176 177 /** This is the const version of transpose(). 178 * 179 * Make sure you read the warning for transpose() ! 180 * 181 * \sa transposeInPlace(), adjoint() */ 182 template<typename Derived> 183 inline typename DenseBase<Derived>::ConstTransposeReturnType 184 DenseBase<Derived>::transpose() const 185 { 186 return ConstTransposeReturnType(derived()); 187 } 188 189 /** \returns an expression of the adjoint (i.e. conjugate transpose) of *this. 190 * 191 * Example: \include MatrixBase_adjoint.cpp 192 * Output: \verbinclude MatrixBase_adjoint.out 193 * 194 * \warning If you want to replace a matrix by its own adjoint, do \b NOT do this: 195 * \code 196 * m = m.adjoint(); // bug!!! caused by aliasing effect 197 * \endcode 198 * Instead, use the adjointInPlace() method: 199 * \code 200 * m.adjointInPlace(); 201 * \endcode 202 * which gives Eigen good opportunities for optimization, or alternatively you can also do: 203 * \code 204 * m = m.adjoint().eval(); 205 * \endcode 206 * 207 * \sa adjointInPlace(), transpose(), conjugate(), class Transpose, class internal::scalar_conjugate_op */ 208 template<typename Derived> 209 inline const typename MatrixBase<Derived>::AdjointReturnType 210 MatrixBase<Derived>::adjoint() const 211 { 212 return AdjointReturnType(this->transpose()); 213 } 214 215 /*************************************************************************** 216 * "in place" transpose implementation 217 ***************************************************************************/ 218 219 namespace internal { 220 221 template<typename MatrixType, 222 bool IsSquare = (MatrixType::RowsAtCompileTime == MatrixType::ColsAtCompileTime) && MatrixType::RowsAtCompileTime!=Dynamic, 223 bool MatchPacketSize = 224 (int(MatrixType::RowsAtCompileTime) == int(internal::packet_traits<typename MatrixType::Scalar>::size)) 225 && (internal::evaluator<MatrixType>::Flags&PacketAccessBit) > 226 struct inplace_transpose_selector; 227 228 template<typename MatrixType> 229 struct inplace_transpose_selector<MatrixType,true,false> { // square matrix 230 static void run(MatrixType& m) { 231 m.matrix().template triangularView<StrictlyUpper>().swap(m.matrix().transpose()); 232 } 233 }; 234 235 // TODO: vectorized path is currently limited to LargestPacketSize x LargestPacketSize cases only. 236 template<typename MatrixType> 237 struct inplace_transpose_selector<MatrixType,true,true> { // PacketSize x PacketSize 238 static void run(MatrixType& m) { 239 typedef typename MatrixType::Scalar Scalar; 240 typedef typename internal::packet_traits<typename MatrixType::Scalar>::type Packet; 241 const Index PacketSize = internal::packet_traits<Scalar>::size; 242 const Index Alignment = internal::evaluator<MatrixType>::Alignment; 243 PacketBlock<Packet> A; 244 for (Index i=0; i<PacketSize; ++i) 245 A.packet[i] = m.template packetByOuterInner<Alignment>(i,0); 246 internal::ptranspose(A); 247 for (Index i=0; i<PacketSize; ++i) 248 m.template writePacket<Alignment>(m.rowIndexByOuterInner(i,0), m.colIndexByOuterInner(i,0), A.packet[i]); 249 } 250 }; 251 252 template<typename MatrixType,bool MatchPacketSize> 253 struct inplace_transpose_selector<MatrixType,false,MatchPacketSize> { // non square matrix 254 static void run(MatrixType& m) { 255 if (m.rows()==m.cols()) 256 m.matrix().template triangularView<StrictlyUpper>().swap(m.matrix().transpose()); 257 else 258 m = m.transpose().eval(); 259 } 260 }; 261 262 } // end namespace internal 263 264 /** This is the "in place" version of transpose(): it replaces \c *this by its own transpose. 265 * Thus, doing 266 * \code 267 * m.transposeInPlace(); 268 * \endcode 269 * has the same effect on m as doing 270 * \code 271 * m = m.transpose().eval(); 272 * \endcode 273 * and is faster and also safer because in the latter line of code, forgetting the eval() results 274 * in a bug caused by \ref TopicAliasing "aliasing". 275 * 276 * Notice however that this method is only useful if you want to replace a matrix by its own transpose. 277 * If you just need the transpose of a matrix, use transpose(). 278 * 279 * \note if the matrix is not square, then \c *this must be a resizable matrix. 280 * This excludes (non-square) fixed-size matrices, block-expressions and maps. 281 * 282 * \sa transpose(), adjoint(), adjointInPlace() */ 283 template<typename Derived> 284 inline void DenseBase<Derived>::transposeInPlace() 285 { 286 eigen_assert((rows() == cols() || (RowsAtCompileTime == Dynamic && ColsAtCompileTime == Dynamic)) 287 && "transposeInPlace() called on a non-square non-resizable matrix"); 288 internal::inplace_transpose_selector<Derived>::run(derived()); 289 } 290 291 /*************************************************************************** 292 * "in place" adjoint implementation 293 ***************************************************************************/ 294 295 /** This is the "in place" version of adjoint(): it replaces \c *this by its own transpose. 296 * Thus, doing 297 * \code 298 * m.adjointInPlace(); 299 * \endcode 300 * has the same effect on m as doing 301 * \code 302 * m = m.adjoint().eval(); 303 * \endcode 304 * and is faster and also safer because in the latter line of code, forgetting the eval() results 305 * in a bug caused by aliasing. 306 * 307 * Notice however that this method is only useful if you want to replace a matrix by its own adjoint. 308 * If you just need the adjoint of a matrix, use adjoint(). 309 * 310 * \note if the matrix is not square, then \c *this must be a resizable matrix. 311 * This excludes (non-square) fixed-size matrices, block-expressions and maps. 312 * 313 * \sa transpose(), adjoint(), transposeInPlace() */ 314 template<typename Derived> 315 inline void MatrixBase<Derived>::adjointInPlace() 316 { 317 derived() = adjoint().eval(); 318 } 319 320 #ifndef EIGEN_NO_DEBUG 321 322 // The following is to detect aliasing problems in most common cases. 323 324 namespace internal { 325 326 template<bool DestIsTransposed, typename OtherDerived> 327 struct check_transpose_aliasing_compile_time_selector 328 { 329 enum { ret = bool(blas_traits<OtherDerived>::IsTransposed) != DestIsTransposed }; 330 }; 331 332 template<bool DestIsTransposed, typename BinOp, typename DerivedA, typename DerivedB> 333 struct check_transpose_aliasing_compile_time_selector<DestIsTransposed,CwiseBinaryOp<BinOp,DerivedA,DerivedB> > 334 { 335 enum { ret = bool(blas_traits<DerivedA>::IsTransposed) != DestIsTransposed 336 || bool(blas_traits<DerivedB>::IsTransposed) != DestIsTransposed 337 }; 338 }; 339 340 template<typename Scalar, bool DestIsTransposed, typename OtherDerived> 341 struct check_transpose_aliasing_run_time_selector 342 { 343 static bool run(const Scalar* dest, const OtherDerived& src) 344 { 345 return (bool(blas_traits<OtherDerived>::IsTransposed) != DestIsTransposed) && (dest!=0 && dest==(const Scalar*)extract_data(src)); 346 } 347 }; 348 349 template<typename Scalar, bool DestIsTransposed, typename BinOp, typename DerivedA, typename DerivedB> 350 struct check_transpose_aliasing_run_time_selector<Scalar,DestIsTransposed,CwiseBinaryOp<BinOp,DerivedA,DerivedB> > 351 { 352 static bool run(const Scalar* dest, const CwiseBinaryOp<BinOp,DerivedA,DerivedB>& src) 353 { 354 return ((blas_traits<DerivedA>::IsTransposed != DestIsTransposed) && (dest!=0 && dest==(const Scalar*)extract_data(src.lhs()))) 355 || ((blas_traits<DerivedB>::IsTransposed != DestIsTransposed) && (dest!=0 && dest==(const Scalar*)extract_data(src.rhs()))); 356 } 357 }; 358 359 // the following selector, checkTransposeAliasing_impl, based on MightHaveTransposeAliasing, 360 // is because when the condition controlling the assert is known at compile time, ICC emits a warning. 361 // This is actually a good warning: in expressions that don't have any transposing, the condition is 362 // known at compile time to be false, and using that, we can avoid generating the code of the assert again 363 // and again for all these expressions that don't need it. 364 365 template<typename Derived, typename OtherDerived, 366 bool MightHaveTransposeAliasing 367 = check_transpose_aliasing_compile_time_selector 368 <blas_traits<Derived>::IsTransposed,OtherDerived>::ret 369 > 370 struct checkTransposeAliasing_impl 371 { 372 static void run(const Derived& dst, const OtherDerived& other) 373 { 374 eigen_assert((!check_transpose_aliasing_run_time_selector 375 <typename Derived::Scalar,blas_traits<Derived>::IsTransposed,OtherDerived> 376 ::run(extract_data(dst), other)) 377 && "aliasing detected during transposition, use transposeInPlace() " 378 "or evaluate the rhs into a temporary using .eval()"); 379 380 } 381 }; 382 383 template<typename Derived, typename OtherDerived> 384 struct checkTransposeAliasing_impl<Derived, OtherDerived, false> 385 { 386 static void run(const Derived&, const OtherDerived&) 387 { 388 } 389 }; 390 391 template<typename Dst, typename Src> 392 void check_for_aliasing(const Dst &dst, const Src &src) 393 { 394 internal::checkTransposeAliasing_impl<Dst, Src>::run(dst, src); 395 } 396 397 } // end namespace internal 398 399 #endif // EIGEN_NO_DEBUG 400 401 } // end namespace Eigen 402 403 #endif // EIGEN_TRANSPOSE_H 404
