Transpose.h
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@gmail.com>
5 // Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud@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 
30 namespace internal {
31 template<typename MatrixType>
32 struct traits<Transpose<MatrixType> > : traits<MatrixType>
33 {
34  typedef typename MatrixType::Scalar Scalar;
35  typedef typename nested<MatrixType>::type MatrixTypeNested;
36  typedef typename remove_reference<MatrixTypeNested>::type MatrixTypeNestedPlain;
37  typedef typename traits<MatrixType>::StorageKind StorageKind;
38  typedef typename traits<MatrixType>::XprKind XprKind;
39  enum {
40  RowsAtCompileTime = MatrixType::ColsAtCompileTime,
41  ColsAtCompileTime = MatrixType::RowsAtCompileTime,
42  MaxRowsAtCompileTime = MatrixType::MaxColsAtCompileTime,
43  MaxColsAtCompileTime = MatrixType::MaxRowsAtCompileTime,
44  FlagsLvalueBit = is_lvalue<MatrixType>::value ? LvalueBit : 0,
45  Flags0 = MatrixTypeNestedPlain::Flags & ~(LvalueBit | NestByRefBit),
46  Flags1 = Flags0 | FlagsLvalueBit,
47  Flags = Flags1 ^ RowMajorBit,
48  CoeffReadCost = MatrixTypeNestedPlain::CoeffReadCost,
49  InnerStrideAtCompileTime = inner_stride_at_compile_time<MatrixType>::ret,
50  OuterStrideAtCompileTime = outer_stride_at_compile_time<MatrixType>::ret
51  };
52 };
53 }
54 
55 template<typename MatrixType, typename StorageKind> class TransposeImpl;
56 
57 template<typename MatrixType> class Transpose
58  : public TransposeImpl<MatrixType,typename internal::traits<MatrixType>::StorageKind>
59 {
60  public:
61 
62  typedef typename TransposeImpl<MatrixType,typename internal::traits<MatrixType>::StorageKind>::Base Base;
63  EIGEN_GENERIC_PUBLIC_INTERFACE(Transpose)
64 
65  inline Transpose(MatrixType& matrix) : m_matrix(matrix) {}
66 
67  EIGEN_INHERIT_ASSIGNMENT_OPERATORS(Transpose)
68 
69  inline Index rows() const { return m_matrix.cols(); }
70  inline Index cols() const { return m_matrix.rows(); }
71 
73  const typename internal::remove_all<typename MatrixType::Nested>::type&
74  nestedExpression() const { return m_matrix; }
75 
77  typename internal::remove_all<typename MatrixType::Nested>::type&
78  nestedExpression() { return m_matrix.const_cast_derived(); }
79 
80  protected:
81  typename MatrixType::Nested m_matrix;
82 };
83 
84 namespace internal {
85 
86 template<typename MatrixType, bool HasDirectAccess = has_direct_access<MatrixType>::ret>
87 struct TransposeImpl_base
88 {
89  typedef typename dense_xpr_base<Transpose<MatrixType> >::type type;
90 };
91 
92 template<typename MatrixType>
93 struct TransposeImpl_base<MatrixType, false>
94 {
95  typedef typename dense_xpr_base<Transpose<MatrixType> >::type type;
96 };
97 
98 } // end namespace internal
99 
100 template<typename MatrixType> class TransposeImpl<MatrixType,Dense>
101  : public internal::TransposeImpl_base<MatrixType>::type
102 {
103  public:
104 
105  typedef typename internal::TransposeImpl_base<MatrixType>::type Base;
106  EIGEN_DENSE_PUBLIC_INTERFACE(Transpose<MatrixType>)
107  EIGEN_INHERIT_ASSIGNMENT_OPERATORS(TransposeImpl)
108 
109  inline Index innerStride() const { return derived().nestedExpression().innerStride(); }
110  inline Index outerStride() const { return derived().nestedExpression().outerStride(); }
111 
112  typedef typename internal::conditional<
113  internal::is_lvalue<MatrixType>::value,
114  Scalar,
115  const Scalar
116  >::type ScalarWithConstIfNotLvalue;
117 
118  inline ScalarWithConstIfNotLvalue* data() { return derived().nestedExpression().data(); }
119  inline const Scalar* data() const { return derived().nestedExpression().data(); }
120 
121  inline ScalarWithConstIfNotLvalue& coeffRef(Index row, Index col)
122  {
123  EIGEN_STATIC_ASSERT_LVALUE(MatrixType)
124  return derived().nestedExpression().const_cast_derived().coeffRef(col, row);
125  }
126 
127  inline ScalarWithConstIfNotLvalue& coeffRef(Index index)
128  {
129  EIGEN_STATIC_ASSERT_LVALUE(MatrixType)
130  return derived().nestedExpression().const_cast_derived().coeffRef(index);
131  }
132 
133  inline const Scalar& coeffRef(Index row, Index col) const
134  {
135  return derived().nestedExpression().coeffRef(col, row);
136  }
137 
138  inline const Scalar& coeffRef(Index index) const
139  {
140  return derived().nestedExpression().coeffRef(index);
141  }
142 
143  inline CoeffReturnType coeff(Index row, Index col) const
144  {
145  return derived().nestedExpression().coeff(col, row);
146  }
147 
148  inline CoeffReturnType coeff(Index index) const
149  {
150  return derived().nestedExpression().coeff(index);
151  }
152 
153  template<int LoadMode>
154  inline const PacketScalar packet(Index row, Index col) const
155  {
156  return derived().nestedExpression().template packet<LoadMode>(col, row);
157  }
158 
159  template<int LoadMode>
160  inline void writePacket(Index row, Index col, const PacketScalar& x)
161  {
162  derived().nestedExpression().const_cast_derived().template writePacket<LoadMode>(col, row, x);
163  }
164 
165  template<int LoadMode>
166  inline const PacketScalar packet(Index index) const
167  {
168  return derived().nestedExpression().template packet<LoadMode>(index);
169  }
170 
171  template<int LoadMode>
172  inline void writePacket(Index index, const PacketScalar& x)
173  {
174  derived().nestedExpression().const_cast_derived().template writePacket<LoadMode>(index, x);
175  }
176 };
177 
197 template<typename Derived>
198 inline Transpose<Derived>
200 {
201  return derived();
202 }
203 
209 template<typename Derived>
212 {
213  return ConstTransposeReturnType(derived());
214 }
215 
235 template<typename Derived>
236 inline const typename MatrixBase<Derived>::AdjointReturnType
238 {
239  return this->transpose(); // in the complex case, the .conjugate() is be implicit here
240  // due to implicit conversion to return type
241 }
242 
243 /***************************************************************************
244 * "in place" transpose implementation
245 ***************************************************************************/
246 
247 namespace internal {
248 
249 template<typename MatrixType,
250  bool IsSquare = (MatrixType::RowsAtCompileTime == MatrixType::ColsAtCompileTime) && MatrixType::RowsAtCompileTime!=Dynamic>
251 struct inplace_transpose_selector;
252 
253 template<typename MatrixType>
254 struct inplace_transpose_selector<MatrixType,true> { // square matrix
255  static void run(MatrixType& m) {
256  m.matrix().template triangularView<StrictlyUpper>().swap(m.matrix().transpose());
257  }
258 };
259 
260 template<typename MatrixType>
261 struct inplace_transpose_selector<MatrixType,false> { // non square matrix
262  static void run(MatrixType& m) {
263  if (m.rows()==m.cols())
264  m.matrix().template triangularView<StrictlyUpper>().swap(m.matrix().transpose());
265  else
266  m = m.transpose().eval();
267  }
268 };
269 
270 } // end namespace internal
271 
290 template<typename Derived>
292 {
293  internal::inplace_transpose_selector<Derived>::run(derived());
294 }
295 
296 /***************************************************************************
297 * "in place" adjoint implementation
298 ***************************************************************************/
299 
318 template<typename Derived>
320 {
321  derived() = adjoint().eval();
322 }
323 
324 #ifndef EIGEN_NO_DEBUG
325 
326 // The following is to detect aliasing problems in most common cases.
327 
328 namespace internal {
329 
330 template<typename BinOp,typename NestedXpr,typename Rhs>
331 struct blas_traits<SelfCwiseBinaryOp<BinOp,NestedXpr,Rhs> >
332  : blas_traits<NestedXpr>
333 {
334  typedef SelfCwiseBinaryOp<BinOp,NestedXpr,Rhs> XprType;
335  static inline const XprType extract(const XprType& x) { return x; }
336 };
337 
338 template<bool DestIsTransposed, typename OtherDerived>
339 struct check_transpose_aliasing_compile_time_selector
340 {
341  enum { ret = bool(blas_traits<OtherDerived>::IsTransposed) != DestIsTransposed };
342 };
343 
344 template<bool DestIsTransposed, typename BinOp, typename DerivedA, typename DerivedB>
345 struct check_transpose_aliasing_compile_time_selector<DestIsTransposed,CwiseBinaryOp<BinOp,DerivedA,DerivedB> >
346 {
347  enum { ret = bool(blas_traits<DerivedA>::IsTransposed) != DestIsTransposed
348  || bool(blas_traits<DerivedB>::IsTransposed) != DestIsTransposed
349  };
350 };
351 
352 template<typename Scalar, bool DestIsTransposed, typename OtherDerived>
353 struct check_transpose_aliasing_run_time_selector
354 {
355  static bool run(const Scalar* dest, const OtherDerived& src)
356  {
357  return (bool(blas_traits<OtherDerived>::IsTransposed) != DestIsTransposed) && (dest!=0 && dest==(const Scalar*)extract_data(src));
358  }
359 };
360 
361 template<typename Scalar, bool DestIsTransposed, typename BinOp, typename DerivedA, typename DerivedB>
362 struct check_transpose_aliasing_run_time_selector<Scalar,DestIsTransposed,CwiseBinaryOp<BinOp,DerivedA,DerivedB> >
363 {
364  static bool run(const Scalar* dest, const CwiseBinaryOp<BinOp,DerivedA,DerivedB>& src)
365  {
366  return ((blas_traits<DerivedA>::IsTransposed != DestIsTransposed) && (dest!=0 && dest==(const Scalar*)extract_data(src.lhs())))
367  || ((blas_traits<DerivedB>::IsTransposed != DestIsTransposed) && (dest!=0 && dest==(const Scalar*)extract_data(src.rhs())));
368  }
369 };
370 
371 // the following selector, checkTransposeAliasing_impl, based on MightHaveTransposeAliasing,
372 // is because when the condition controlling the assert is known at compile time, ICC emits a warning.
373 // This is actually a good warning: in expressions that don't have any transposing, the condition is
374 // known at compile time to be false, and using that, we can avoid generating the code of the assert again
375 // and again for all these expressions that don't need it.
376 
377 template<typename Derived, typename OtherDerived,
378  bool MightHaveTransposeAliasing
379  = check_transpose_aliasing_compile_time_selector
380  <blas_traits<Derived>::IsTransposed,OtherDerived>::ret
381  >
382 struct checkTransposeAliasing_impl
383 {
384  static void run(const Derived& dst, const OtherDerived& other)
385  {
386  eigen_assert((!check_transpose_aliasing_run_time_selector
387  <typename Derived::Scalar,blas_traits<Derived>::IsTransposed,OtherDerived>
388  ::run(extract_data(dst), other))
389  && "aliasing detected during tranposition, use transposeInPlace() "
390  "or evaluate the rhs into a temporary using .eval()");
391 
392  }
393 };
394 
395 template<typename Derived, typename OtherDerived>
396 struct checkTransposeAliasing_impl<Derived, OtherDerived, false>
397 {
398  static void run(const Derived&, const OtherDerived&)
399  {
400  }
401 };
402 
403 } // end namespace internal
404 
405 template<typename Derived>
406 template<typename OtherDerived>
407 void DenseBase<Derived>::checkTransposeAliasing(const OtherDerived& other) const
408 {
409  internal::checkTransposeAliasing_impl<Derived, OtherDerived>::run(derived(), other);
410 }
411 #endif
412 
413 } // end namespace Eigen
414 
415 #endif // EIGEN_TRANSPOSE_H