Make permutation compatible with sparse matrices

3 files changed, 25 insertions, 11 deletions

diff --git a/Eigen/src/Core/PermutationMatrix.h b/Eigen/src/Core/PermutationMatrix.h
index 5d648c68c..84d64edb3 100644
--- a/Eigen/src/Core/PermutationMatrix.h
+++ b/Eigen/src/Core/PermutationMatrix.h
@@ -13,7 +13,8 @@
 
 namespace Eigen { 
 
-template<int RowCol,typename IndicesType,typename MatrixType, typename StorageKind> class PermutedImpl;
+// TODO: this does not seems to be needed at all:
+// template<int RowCol,typename IndicesType,typename MatrixType, typename StorageKind> class PermutedImpl;
 
 /** \class PermutationBase
   * \ingroup Core_Module
@@ -276,6 +277,7 @@ template<int SizeAtCompileTime, int MaxSizeAtCompileTime, typename _StorageIndex
 struct traits<PermutationMatrix<SizeAtCompileTime, MaxSizeAtCompileTime, _StorageIndexType> >
  : traits<Matrix<_StorageIndexType,SizeAtCompileTime,SizeAtCompileTime,0,MaxSizeAtCompileTime,MaxSizeAtCompileTime> >
 {
+  typedef PermutationStorage StorageKind;
   typedef Matrix<_StorageIndexType, SizeAtCompileTime, 1, 0, MaxSizeAtCompileTime, 1> IndicesType;
   typedef typename IndicesType::Index Index;
   typedef _StorageIndexType StorageIndexType;
@@ -397,6 +399,7 @@ template<int SizeAtCompileTime, int MaxSizeAtCompileTime, typename _StorageIndex
 struct traits<Map<PermutationMatrix<SizeAtCompileTime, MaxSizeAtCompileTime, _StorageIndexType>,_PacketAccess> >
  : traits<Matrix<_StorageIndexType,SizeAtCompileTime,SizeAtCompileTime,0,MaxSizeAtCompileTime,MaxSizeAtCompileTime> >
 {
+  typedef PermutationStorage StorageKind;
   typedef Map<const Matrix<_StorageIndexType, SizeAtCompileTime, 1, 0, MaxSizeAtCompileTime, 1>, _PacketAccess> IndicesType;
   typedef typename IndicesType::Index Index;
   typedef _StorageIndexType StorageIndexType;
@@ -468,8 +471,6 @@ class Map<PermutationMatrix<SizeAtCompileTime, MaxSizeAtCompileTime, _StorageInd
   * \sa class PermutationBase, class PermutationMatrix
   */
 
-struct PermutationStorage {};
-
 template<typename _IndicesType> class TranspositionsWrapper;
 namespace internal {
 template<typename _IndicesType>
@@ -665,6 +666,8 @@ struct traits<Transpose<PermutationBase<Derived> > >
 
 } // end namespace internal
 
+// TODO: the specificties should be handled by the evaluator,
+// at the very least we should only specialize TransposeImpl
 template<typename Derived>
 class Transpose<PermutationBase<Derived> >
   : public EigenBase<Transpose<PermutationBase<Derived> > >
diff --git a/Eigen/src/Core/util/Constants.h b/Eigen/src/Core/util/Constants.h
index 3ab8d0ed3..c0463583d 100644
--- a/Eigen/src/Core/util/Constants.h
+++ b/Eigen/src/Core/util/Constants.h
@@ -443,6 +443,9 @@ enum Action {GetAction, SetAction};
 /** The type used to identify a dense storage. */
 struct Dense {};
 
+/** The type used to identify a permutation storage. */
+struct PermutationStorage {};
+
 /** The type used to identify a matrix expression */
 struct MatrixXpr {};
 
diff --git a/Eigen/src/Core/util/XprHelper.h b/Eigen/src/Core/util/XprHelper.h
index 7779fb3fa..5ed3b39b7 100644
--- a/Eigen/src/Core/util/XprHelper.h
+++ b/Eigen/src/Core/util/XprHelper.h
@@ -557,18 +557,26 @@ template <typename B, typename ScalarA, typename ScalarB> struct cwise_promote_s
   *  K * dense        -> dense
   *  diag * K         -> K
   *  K * diag         -> K
+  *  Perm * K         -> K
+  * K * Perm          -> K
   * \endcode
   */
 template <typename A, typename B, int ProductTag> struct product_promote_storage_type;
 
-template <typename A, int ProductTag> struct product_promote_storage_type<A,            A,              ProductTag> { typedef A     ret;};
-template <int ProductTag>             struct product_promote_storage_type<Dense,        Dense,          ProductTag> { typedef Dense ret;};
-template <typename A, int ProductTag> struct product_promote_storage_type<A,            Dense,          ProductTag> { typedef Dense ret; };
-template <typename B, int ProductTag> struct product_promote_storage_type<Dense,        B,              ProductTag> { typedef Dense ret; };
-template <typename A, int ProductTag> struct product_promote_storage_type<A,            DiagonalShape,  ProductTag> { typedef A ret; };
-template <typename B, int ProductTag> struct product_promote_storage_type<DiagonalShape,B,              ProductTag> { typedef B ret; };
-template <int ProductTag>             struct product_promote_storage_type<Dense,        DiagonalShape,  ProductTag> { typedef Dense ret; };
-template <int ProductTag>             struct product_promote_storage_type<DiagonalShape,Dense,          ProductTag> { typedef Dense ret; };
+template <typename A, int ProductTag> struct product_promote_storage_type<A,                  A,                  ProductTag> { typedef A     ret;};
+template <int ProductTag>             struct product_promote_storage_type<Dense,              Dense,              ProductTag> { typedef Dense ret;};
+template <typename A, int ProductTag> struct product_promote_storage_type<A,                  Dense,              ProductTag> { typedef Dense ret; };
+template <typename B, int ProductTag> struct product_promote_storage_type<Dense,              B,                  ProductTag> { typedef Dense ret; };
+
+template <typename A, int ProductTag> struct product_promote_storage_type<A,                  DiagonalShape,      ProductTag> { typedef A ret; };
+template <typename B, int ProductTag> struct product_promote_storage_type<DiagonalShape,      B,                  ProductTag> { typedef B ret; };
+template <int ProductTag>             struct product_promote_storage_type<Dense,              DiagonalShape,      ProductTag> { typedef Dense ret; };
+template <int ProductTag>             struct product_promote_storage_type<DiagonalShape,      Dense,              ProductTag> { typedef Dense ret; };
+
+template <typename A, int ProductTag> struct product_promote_storage_type<A,                  PermutationStorage, ProductTag> { typedef A ret; };
+template <typename B, int ProductTag> struct product_promote_storage_type<PermutationStorage, B,                  ProductTag> { typedef B ret; };
+template <int ProductTag>             struct product_promote_storage_type<Dense,              PermutationStorage, ProductTag> { typedef Dense ret; };
+template <int ProductTag>             struct product_promote_storage_type<PermutationStorage, Dense,              ProductTag> { typedef Dense ret; };
 
 /** \internal gives the plain matrix or array type to store a row/column/diagonal of a matrix type.
   * \param Scalar optional parameter allowing to pass a different scalar type than the one of the MatrixType.