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 
108  inline Index innerStride() const { return derived().nestedExpression().innerStride(); }
109  inline Index outerStride() const { return derived().nestedExpression().outerStride(); }
110 
111  typedef typename internal::conditional<
112  internal::is_lvalue<MatrixType>::value,
113  Scalar,
114  const Scalar
115  >::type ScalarWithConstIfNotLvalue;
116 
117  inline ScalarWithConstIfNotLvalue* data() { return derived().nestedExpression().data(); }
118  inline const Scalar* data() const { return derived().nestedExpression().data(); }
119 
120  inline ScalarWithConstIfNotLvalue& coeffRef(Index row, Index col)
121  {
122  EIGEN_STATIC_ASSERT_LVALUE(MatrixType)
123  return derived().nestedExpression().const_cast_derived().coeffRef(col, row);
124  }
125 
126  inline ScalarWithConstIfNotLvalue& coeffRef(Index index)
127  {
128  EIGEN_STATIC_ASSERT_LVALUE(MatrixType)
129  return derived().nestedExpression().const_cast_derived().coeffRef(index);
130  }
131 
132  inline const Scalar& coeffRef(Index row, Index col) const
133  {
134  return derived().nestedExpression().coeffRef(col, row);
135  }
136 
137  inline const Scalar& coeffRef(Index index) const
138  {
139  return derived().nestedExpression().coeffRef(index);
140  }
141 
142  inline CoeffReturnType coeff(Index row, Index col) const
143  {
144  return derived().nestedExpression().coeff(col, row);
145  }
146 
147  inline CoeffReturnType coeff(Index index) const
148  {
149  return derived().nestedExpression().coeff(index);
150  }
151 
152  template<int LoadMode>
153  inline const PacketScalar packet(Index row, Index col) const
154  {
155  return derived().nestedExpression().template packet<LoadMode>(col, row);
156  }
157 
158  template<int LoadMode>
159  inline void writePacket(Index row, Index col, const PacketScalar& x)
160  {
161  derived().nestedExpression().const_cast_derived().template writePacket<LoadMode>(col, row, x);
162  }
163 
164  template<int LoadMode>
165  inline const PacketScalar packet(Index index) const
166  {
167  return derived().nestedExpression().template packet<LoadMode>(index);
168  }
169 
170  template<int LoadMode>
171  inline void writePacket(Index index, const PacketScalar& x)
172  {
173  derived().nestedExpression().const_cast_derived().template writePacket<LoadMode>(index, x);
174  }
175 };
176 
196 template<typename Derived>
197 inline Transpose<Derived>
199 {
200  return derived();
201 }
202 
208 template<typename Derived>
211 {
212  return ConstTransposeReturnType(derived());
213 }
214 
234 template<typename Derived>
235 inline const typename MatrixBase<Derived>::AdjointReturnType
237 {
238  return this->transpose(); // in the complex case, the .conjugate() is be implicit here
239  // due to implicit conversion to return type
240 }
241 
242 /***************************************************************************
243 * "in place" transpose implementation
244 ***************************************************************************/
245 
246 namespace internal {
247 
248 template<typename MatrixType,
249  bool IsSquare = (MatrixType::RowsAtCompileTime == MatrixType::ColsAtCompileTime) && MatrixType::RowsAtCompileTime!=Dynamic>
250 struct inplace_transpose_selector;
251 
252 template<typename MatrixType>
253 struct inplace_transpose_selector<MatrixType,true> { // square matrix
254  static void run(MatrixType& m) {
255  m.template triangularView<StrictlyUpper>().swap(m.transpose());
256  }
257 };
258 
259 template<typename MatrixType>
260 struct inplace_transpose_selector<MatrixType,false> { // non square matrix
261  static void run(MatrixType& m) {
262  if (m.rows()==m.cols())
263  m.template triangularView<StrictlyUpper>().swap(m.transpose());
264  else
265  m = m.transpose().eval();
266  }
267 };
268 
269 } // end namespace internal
270 
289 template<typename Derived>
291 {
292  internal::inplace_transpose_selector<Derived>::run(derived());
293 }
294 
295 /***************************************************************************
296 * "in place" adjoint implementation
297 ***************************************************************************/
298 
317 template<typename Derived>
319 {
320  derived() = adjoint().eval();
321 }
322 
323 #ifndef EIGEN_NO_DEBUG
324 
325 // The following is to detect aliasing problems in most common cases.
326 
327 namespace internal {
328 
329 template<typename BinOp,typename NestedXpr,typename Rhs>
330 struct blas_traits<SelfCwiseBinaryOp<BinOp,NestedXpr,Rhs> >
331  : blas_traits<NestedXpr>
332 {
333  typedef SelfCwiseBinaryOp<BinOp,NestedXpr,Rhs> XprType;
334  static inline const XprType extract(const XprType& x) { return x; }
335 };
336 
337 template<bool DestIsTransposed, typename OtherDerived>
338 struct check_transpose_aliasing_compile_time_selector
339 {
340  enum { ret = bool(blas_traits<OtherDerived>::IsTransposed) != DestIsTransposed };
341 };
342 
343 template<bool DestIsTransposed, typename BinOp, typename DerivedA, typename DerivedB>
344 struct check_transpose_aliasing_compile_time_selector<DestIsTransposed,CwiseBinaryOp<BinOp,DerivedA,DerivedB> >
345 {
346  enum { ret = bool(blas_traits<DerivedA>::IsTransposed) != DestIsTransposed
347  || bool(blas_traits<DerivedB>::IsTransposed) != DestIsTransposed
348  };
349 };
350 
351 template<typename Scalar, bool DestIsTransposed, typename OtherDerived>
352 struct check_transpose_aliasing_run_time_selector
353 {
354  static bool run(const Scalar* dest, const OtherDerived& src)
355  {
356  return (bool(blas_traits<OtherDerived>::IsTransposed) != DestIsTransposed) && (dest!=0 && dest==(const Scalar*)extract_data(src));
357  }
358 };
359 
360 template<typename Scalar, bool DestIsTransposed, typename BinOp, typename DerivedA, typename DerivedB>
361 struct check_transpose_aliasing_run_time_selector<Scalar,DestIsTransposed,CwiseBinaryOp<BinOp,DerivedA,DerivedB> >
362 {
363  static bool run(const Scalar* dest, const CwiseBinaryOp<BinOp,DerivedA,DerivedB>& src)
364  {
365  return ((blas_traits<DerivedA>::IsTransposed != DestIsTransposed) && (dest!=0 && dest==(const Scalar*)extract_data(src.lhs())))
366  || ((blas_traits<DerivedB>::IsTransposed != DestIsTransposed) && (dest!=0 && dest==(const Scalar*)extract_data(src.rhs())));
367  }
368 };
369 
370 // the following selector, checkTransposeAliasing_impl, based on MightHaveTransposeAliasing,
371 // is because when the condition controlling the assert is known at compile time, ICC emits a warning.
372 // This is actually a good warning: in expressions that don't have any transposing, the condition is
373 // known at compile time to be false, and using that, we can avoid generating the code of the assert again
374 // and again for all these expressions that don't need it.
375 
376 template<typename Derived, typename OtherDerived,
377  bool MightHaveTransposeAliasing
378  = check_transpose_aliasing_compile_time_selector
379  <blas_traits<Derived>::IsTransposed,OtherDerived>::ret
380  >
381 struct checkTransposeAliasing_impl
382 {
383  static void run(const Derived& dst, const OtherDerived& other)
384  {
385  eigen_assert((!check_transpose_aliasing_run_time_selector
386  <typename Derived::Scalar,blas_traits<Derived>::IsTransposed,OtherDerived>
387  ::run(extract_data(dst), other))
388  && "aliasing detected during tranposition, use transposeInPlace() "
389  "or evaluate the rhs into a temporary using .eval()");
390 
391  }
392 };
393 
394 template<typename Derived, typename OtherDerived>
395 struct checkTransposeAliasing_impl<Derived, OtherDerived, false>
396 {
397  static void run(const Derived&, const OtherDerived&)
398  {
399  }
400 };
401 
402 } // end namespace internal
403 
404 template<typename Derived>
405 template<typename OtherDerived>
406 void DenseBase<Derived>::checkTransposeAliasing(const OtherDerived& other) const
407 {
408  internal::checkTransposeAliasing_impl<Derived, OtherDerived>::run(derived(), other);
409 }
410 #endif
411 
412 } // end namespace Eigen
413 
414 #endif // EIGEN_TRANSPOSE_H