Implement generic scalar*expr and expr*scalar operator based on scalar_product_traits.

This is especially useful for custom scalar types, e.g., to enable float*expr<multi_prec> without conversion.

7 files changed, 46 insertions, 53 deletions

diff --git a/Eigen/src/Core/ArrayBase.h b/Eigen/src/Core/ArrayBase.h
index 57333af1a..3d9c37bf6 100644
--- a/Eigen/src/Core/ArrayBase.h
+++ b/Eigen/src/Core/ArrayBase.h
@@ -52,8 +52,6 @@ template<typename Derived> class ArrayBase
     typedef typename NumTraits<Scalar>::Real RealScalar;
 
     typedef DenseBase<Derived> Base;
-    using Base::operator*;
-    using Base::operator/;
     using Base::RowsAtCompileTime;
     using Base::ColsAtCompileTime;
     using Base::SizeAtCompileTime;
diff --git a/Eigen/src/Core/DenseBase.h b/Eigen/src/Core/DenseBase.h
index da80e0438..126187aa2 100644
--- a/Eigen/src/Core/DenseBase.h
+++ b/Eigen/src/Core/DenseBase.h
@@ -75,8 +75,6 @@ template<typename Derived> class DenseBase
     typedef typename NumTraits<Scalar>::Real RealScalar;
     typedef internal::special_scalar_op_base<Derived,Scalar,RealScalar, DenseCoeffsBase<Derived> > Base;
 
-    using Base::operator*;
-    using Base::operator/;
     using Base::derived;
     using Base::const_cast_derived;
     using Base::rows;
diff --git a/Eigen/src/Core/MatrixBase.h b/Eigen/src/Core/MatrixBase.h
index 1e66b4e1b..b8b7f458f 100644
--- a/Eigen/src/Core/MatrixBase.h
+++ b/Eigen/src/Core/MatrixBase.h
@@ -80,8 +80,6 @@ template<typename Derived> class MatrixBase
     using Base::operator-=;
     using Base::operator*=;
     using Base::operator/=;
-    using Base::operator*;
-    using Base::operator/;
 
     typedef typename Base::CoeffReturnType CoeffReturnType;
     typedef typename Base::ConstTransposeReturnType ConstTransposeReturnType;
diff --git a/Eigen/src/Core/util/XprHelper.h b/Eigen/src/Core/util/XprHelper.h
index 58723d860..8a7e36253 100644
--- a/Eigen/src/Core/util/XprHelper.h
+++ b/Eigen/src/Core/util/XprHelper.h
@@ -466,34 +466,6 @@ struct special_scalar_op_base : public BaseType
 template<typename Derived,typename Scalar,typename OtherScalar, typename BaseType>
 struct special_scalar_op_base<Derived,Scalar,OtherScalar,BaseType,true>  : public BaseType
 {
-  const CwiseUnaryOp<scalar_multiple2_op<Scalar,OtherScalar>, const Derived>
-  operator*(const OtherScalar& scalar) const
-  {
-#ifdef EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
-    EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
-#endif
-    return CwiseUnaryOp<scalar_multiple2_op<Scalar,OtherScalar>, const Derived>
-      (*static_cast<const Derived*>(this), scalar_multiple2_op<Scalar,OtherScalar>(scalar));
-  }
-
-  inline friend const CwiseUnaryOp<scalar_multiple2_op<Scalar,OtherScalar>, const Derived>
-  operator*(const OtherScalar& scalar, const Derived& matrix)
-  {
-#ifdef EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
-    EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
-#endif
-    return static_cast<const special_scalar_op_base&>(matrix).operator*(scalar);
-  }
-  
-  const CwiseUnaryOp<scalar_quotient2_op<Scalar,OtherScalar>, const Derived>
-  operator/(const OtherScalar& scalar) const
-  {
-#ifdef EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
-    EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
-#endif
-    return CwiseUnaryOp<scalar_quotient2_op<Scalar,OtherScalar>, const Derived>
-      (*static_cast<const Derived*>(this), scalar_quotient2_op<Scalar,OtherScalar>(scalar));
-  }
 };
 
 template<typename XprType, typename CastType> struct cast_return_type
diff --git a/Eigen/src/SparseCore/SparseDenseProduct.h b/Eigen/src/SparseCore/SparseDenseProduct.h
index c9da8a2bb..476796dd7 100644
--- a/Eigen/src/SparseCore/SparseDenseProduct.h
+++ b/Eigen/src/SparseCore/SparseDenseProduct.h
@@ -72,14 +72,16 @@ struct sparse_time_dense_product_impl<SparseLhsType,DenseRhsType,DenseResType, t
 };
 
 // FIXME: what is the purpose of the following specialization? Is it for the BlockedSparse format?
-template<typename T1, typename T2/*, int _Options, typename _StrideType*/>
-struct scalar_product_traits<T1, Ref<T2/*, _Options, _StrideType*/> >
-{
-  enum {
-    Defined = 1
-  };
-  typedef typename CwiseUnaryOp<scalar_multiple2_op<T1, typename T2::Scalar>, T2>::PlainObject ReturnType;
-};
+// -> let's disable it for now as it is conflicting with generic scalar*matrix and matrix*scalar operators
+// template<typename T1, typename T2/*, int _Options, typename _StrideType*/>
+// struct scalar_product_traits<T1, Ref<T2/*, _Options, _StrideType*/> >
+// {
+//   enum {
+//     Defined = 1
+//   };
+//   typedef typename CwiseUnaryOp<scalar_multiple2_op<T1, typename T2::Scalar>, T2>::PlainObject ReturnType;
+// };
+
 template<typename SparseLhsType, typename DenseRhsType, typename DenseResType, typename AlphaType>
 struct sparse_time_dense_product_impl<SparseLhsType,DenseRhsType,DenseResType, AlphaType, ColMajor, true>
 {
diff --git a/Eigen/src/SparseCore/SparseMatrixBase.h b/Eigen/src/SparseCore/SparseMatrixBase.h
index 2a90f40bf..534c56e71 100644
--- a/Eigen/src/SparseCore/SparseMatrixBase.h
+++ b/Eigen/src/SparseCore/SparseMatrixBase.h
@@ -143,8 +143,7 @@ template<typename Derived> class SparseMatrixBase
     { return *static_cast<Derived*>(const_cast<SparseMatrixBase*>(this)); }
 
     typedef internal::special_scalar_op_base<Derived, Scalar, RealScalar, EigenBase<Derived> > Base;
-    using Base::operator*;
-    using Base::operator/;
+
 #endif // not EIGEN_PARSED_BY_DOXYGEN
 
 #define EIGEN_CURRENT_STORAGE_BASE_CLASS Eigen::SparseMatrixBase
diff --git a/Eigen/src/plugins/CommonCwiseUnaryOps.h b/Eigen/src/plugins/CommonCwiseUnaryOps.h
index 050bce03c..67ec601b9 100644
--- a/Eigen/src/plugins/CommonCwiseUnaryOps.h
+++ b/Eigen/src/plugins/CommonCwiseUnaryOps.h
@@ -70,12 +70,18 @@ operator/(const Scalar& scalar) const
   return ScalarQuotient1ReturnType(derived(), internal::scalar_quotient1_op<Scalar>(scalar));
 }
 
-/** Overloaded for efficient real matrix times complex scalar value */
-EIGEN_DEVICE_FUNC
-inline const ScalarComplexMultipleReturnType
-operator*(const std::complex<Scalar>& scalar) const
+/** Overloaded for efficiently multipling with compatible scalar types */
+template <typename T>
+EIGEN_DEVICE_FUNC inline
+typename internal::enable_if<internal::scalar_product_traits<T,Scalar>::Defined,
+                             const CwiseUnaryOp<internal::scalar_multiple2_op<Scalar,T>, const Derived> >::type
+operator*(const T& scalar) const
 {
-  return ScalarComplexMultipleReturnType(derived(), internal::scalar_multiple2_op<Scalar,std::complex<Scalar> >(scalar));
+#ifdef EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
+  EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
+#endif
+  return CwiseUnaryOp<internal::scalar_multiple2_op<Scalar,T>, const Derived>(
+            derived(), internal::scalar_multiple2_op<Scalar,T>(scalar) );
 }
 
 EIGEN_DEVICE_FUNC
@@ -83,11 +89,31 @@ inline friend const ScalarMultipleReturnType
 operator*(const Scalar& scalar, const StorageBaseType& matrix)
 { return matrix*scalar; }
 
-EIGEN_DEVICE_FUNC
-inline friend const CwiseUnaryOp<internal::scalar_multiple2_op<Scalar,std::complex<Scalar> >, const Derived>
-operator*(const std::complex<Scalar>& scalar, const StorageBaseType& matrix)
-{ return matrix*scalar; }
+template <typename T>
+EIGEN_DEVICE_FUNC inline friend
+typename internal::enable_if<internal::scalar_product_traits<Scalar,T>::Defined,
+                             const CwiseUnaryOp<internal::scalar_multiple2_op<Scalar,T>, const Derived> >::type
+operator*(const T& scalar, const StorageBaseType& matrix)
+{
+#ifdef EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
+  EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
+#endif
+  return CwiseUnaryOp<internal::scalar_multiple2_op<Scalar,T>, const Derived>(
+            matrix.derived(), internal::scalar_multiple2_op<Scalar,T>(scalar) );
+}
 
+template <typename T>
+EIGEN_DEVICE_FUNC inline
+typename internal::enable_if<internal::scalar_product_traits<Scalar,T>::Defined,
+                             const CwiseUnaryOp<internal::scalar_quotient2_op<Scalar,T>, const Derived> >::type
+operator/(const T& scalar) const
+{
+#ifdef EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
+  EIGEN_SPECIAL_SCALAR_MULTIPLE_PLUGIN
+#endif
+  return CwiseUnaryOp<internal::scalar_quotient2_op<Scalar,T>, const Derived>(
+            derived(), internal::scalar_quotient2_op<Scalar,T>(scalar) );
+}
 
 template<class NewType> struct CastXpr { typedef typename internal::cast_return_type<Derived,const CwiseUnaryOp<internal::scalar_cast_op<Scalar, NewType>, const Derived> >::type Type; };