ProductBase.h
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00001 // This file is part of Eigen, a lightweight C++ template library
00002 // for linear algebra.
00003 //
00004 // Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud@inria.fr>
00005 //
00006 // Eigen is free software; you can redistribute it and/or
00007 // modify it under the terms of the GNU Lesser General Public
00008 // License as published by the Free Software Foundation; either
00009 // version 3 of the License, or (at your option) any later version.
00010 //
00011 // Alternatively, you can redistribute it and/or
00012 // modify it under the terms of the GNU General Public License as
00013 // published by the Free Software Foundation; either version 2 of
00014 // the License, or (at your option) any later version.
00015 //
00016 // Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
00017 // WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
00018 // FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
00019 // GNU General Public License for more details.
00020 //
00021 // You should have received a copy of the GNU Lesser General Public
00022 // License and a copy of the GNU General Public License along with
00023 // Eigen. If not, see <http://www.gnu.org/licenses/>.
00024 
00025 #ifndef EIGEN_PRODUCTBASE_H
00026 #define EIGEN_PRODUCTBASE_H
00027 
00033 namespace internal {
00034 template<typename Derived, typename _Lhs, typename _Rhs>
00035 struct traits<ProductBase<Derived,_Lhs,_Rhs> >
00036 {
00037   typedef MatrixXpr XprKind;
00038   typedef typename remove_all<_Lhs>::type Lhs;
00039   typedef typename remove_all<_Rhs>::type Rhs;
00040   typedef typename scalar_product_traits<typename Lhs::Scalar, typename Rhs::Scalar>::ReturnType Scalar;
00041   typedef typename promote_storage_type<typename traits<Lhs>::StorageKind,
00042                                            typename traits<Rhs>::StorageKind>::ret StorageKind;
00043   typedef typename promote_index_type<typename traits<Lhs>::Index,
00044                                          typename traits<Rhs>::Index>::type Index;
00045   enum {
00046     RowsAtCompileTime = traits<Lhs>::RowsAtCompileTime,
00047     ColsAtCompileTime = traits<Rhs>::ColsAtCompileTime,
00048     MaxRowsAtCompileTime = traits<Lhs>::MaxRowsAtCompileTime,
00049     MaxColsAtCompileTime = traits<Rhs>::MaxColsAtCompileTime,
00050     Flags = (MaxRowsAtCompileTime==1 ? RowMajorBit : 0)
00051           | EvalBeforeNestingBit | EvalBeforeAssigningBit | NestByRefBit,
00052                   // Note that EvalBeforeNestingBit and NestByRefBit
00053                   // are not used in practice because nested is overloaded for products
00054     CoeffReadCost = 0 // FIXME why is it needed ?
00055   };
00056 };
00057 }
00058 
00059 #define EIGEN_PRODUCT_PUBLIC_INTERFACE(Derived) \
00060   typedef ProductBase<Derived, Lhs, Rhs > Base; \
00061   EIGEN_DENSE_PUBLIC_INTERFACE(Derived) \
00062   typedef typename Base::LhsNested LhsNested; \
00063   typedef typename Base::_LhsNested _LhsNested; \
00064   typedef typename Base::LhsBlasTraits LhsBlasTraits; \
00065   typedef typename Base::ActualLhsType ActualLhsType; \
00066   typedef typename Base::_ActualLhsType _ActualLhsType; \
00067   typedef typename Base::RhsNested RhsNested; \
00068   typedef typename Base::_RhsNested _RhsNested; \
00069   typedef typename Base::RhsBlasTraits RhsBlasTraits; \
00070   typedef typename Base::ActualRhsType ActualRhsType; \
00071   typedef typename Base::_ActualRhsType _ActualRhsType; \
00072   using Base::m_lhs; \
00073   using Base::m_rhs;
00074 
00075 template<typename Derived, typename Lhs, typename Rhs>
00076 class ProductBase : public MatrixBase<Derived>
00077 {
00078   public:
00079     typedef MatrixBase<Derived> Base;
00080     EIGEN_DENSE_PUBLIC_INTERFACE(ProductBase)
00081     
00082     typedef typename Lhs::Nested LhsNested;
00083     typedef typename internal::remove_all<LhsNested>::type _LhsNested;
00084     typedef internal::blas_traits<_LhsNested> LhsBlasTraits;
00085     typedef typename LhsBlasTraits::DirectLinearAccessType ActualLhsType;
00086     typedef typename internal::remove_all<ActualLhsType>::type _ActualLhsType;
00087     typedef typename internal::traits<Lhs>::Scalar LhsScalar;
00088 
00089     typedef typename Rhs::Nested RhsNested;
00090     typedef typename internal::remove_all<RhsNested>::type _RhsNested;
00091     typedef internal::blas_traits<_RhsNested> RhsBlasTraits;
00092     typedef typename RhsBlasTraits::DirectLinearAccessType ActualRhsType;
00093     typedef typename internal::remove_all<ActualRhsType>::type _ActualRhsType;
00094     typedef typename internal::traits<Rhs>::Scalar RhsScalar;
00095 
00096     // Diagonal of a product: no need to evaluate the arguments because they are going to be evaluated only once
00097     typedef CoeffBasedProduct<LhsNested, RhsNested, 0> FullyLazyCoeffBaseProductType;
00098 
00099   public:
00100 
00101     typedef typename Base::PlainObject PlainObject;
00102 
00103     ProductBase(const Lhs& lhs, const Rhs& rhs)
00104       : m_lhs(lhs), m_rhs(rhs)
00105     {
00106       eigen_assert(lhs.cols() == rhs.rows()
00107         && "invalid matrix product"
00108         && "if you wanted a coeff-wise or a dot product use the respective explicit functions");
00109     }
00110 
00111     inline Index rows() const { return m_lhs.rows(); }
00112     inline Index cols() const { return m_rhs.cols(); }
00113 
00114     template<typename Dest>
00115     inline void evalTo(Dest& dst) const { dst.setZero(); scaleAndAddTo(dst,Scalar(1)); }
00116 
00117     template<typename Dest>
00118     inline void addTo(Dest& dst) const { scaleAndAddTo(dst,1); }
00119 
00120     template<typename Dest>
00121     inline void subTo(Dest& dst) const { scaleAndAddTo(dst,-1); }
00122 
00123     template<typename Dest>
00124     inline void scaleAndAddTo(Dest& dst,Scalar alpha) const { derived().scaleAndAddTo(dst,alpha); }
00125 
00126     const _LhsNested& lhs() const { return m_lhs; }
00127     const _RhsNested& rhs() const { return m_rhs; }
00128 
00129     // Implicit conversion to the nested type (trigger the evaluation of the product)
00130     operator const PlainObject& () const
00131     {
00132       m_result.resize(m_lhs.rows(), m_rhs.cols());
00133       derived().evalTo(m_result);
00134       return m_result;
00135     }
00136 
00137     const Diagonal<const FullyLazyCoeffBaseProductType,0> diagonal() const
00138     { return FullyLazyCoeffBaseProductType(m_lhs, m_rhs); }
00139 
00140     template<int Index>
00141     const Diagonal<FullyLazyCoeffBaseProductType,Index> diagonal() const
00142     { return FullyLazyCoeffBaseProductType(m_lhs, m_rhs); }
00143 
00144     const Diagonal<FullyLazyCoeffBaseProductType,Dynamic> diagonal(Index index) const
00145     { return FullyLazyCoeffBaseProductType(m_lhs, m_rhs).diagonal(index); }
00146 
00147     // restrict coeff accessors to 1x1 expressions. No need to care about mutators here since this isnt a Lvalue expression
00148     typename Base::CoeffReturnType coeff(Index row, Index col) const
00149     {
00150 #ifdef EIGEN2_SUPPORT
00151       return lhs().row(row).cwiseProduct(rhs().col(col).transpose()).sum();
00152 #else
00153       EIGEN_STATIC_ASSERT_SIZE_1x1(Derived)
00154       eigen_assert(this->rows() == 1 && this->cols() == 1);
00155       return derived().coeff(row,col);
00156 #endif
00157     }
00158 
00159     typename Base::CoeffReturnType coeff(Index i) const
00160     {
00161       EIGEN_STATIC_ASSERT_SIZE_1x1(Derived)
00162       eigen_assert(this->rows() == 1 && this->cols() == 1);
00163       return derived().coeff(i);
00164     }
00165 
00166     const Scalar& coeffRef(Index row, Index col) const
00167     {
00168       EIGEN_STATIC_ASSERT_SIZE_1x1(Derived)
00169       eigen_assert(this->rows() == 1 && this->cols() == 1);
00170       return derived().coeffRef(row,col);
00171     }
00172 
00173     const Scalar& coeffRef(Index i) const
00174     {
00175       EIGEN_STATIC_ASSERT_SIZE_1x1(Derived)
00176       eigen_assert(this->rows() == 1 && this->cols() == 1);
00177       return derived().coeffRef(i);
00178     }
00179 
00180   protected:
00181 
00182     const LhsNested m_lhs;
00183     const RhsNested m_rhs;
00184 
00185     mutable PlainObject m_result;
00186 };
00187 
00188 // here we need to overload the nested rule for products
00189 // such that the nested type is a const reference to a plain matrix
00190 namespace internal {
00191 template<typename Lhs, typename Rhs, int Mode, int N, typename PlainObject>
00192 struct nested<GeneralProduct<Lhs,Rhs,Mode>, N, PlainObject>
00193 {
00194   typedef PlainObject const& type;
00195 };
00196 }
00197 
00198 template<typename NestedProduct>
00199 class ScaledProduct;
00200 
00201 // Note that these two operator* functions are not defined as member
00202 // functions of ProductBase, because, otherwise we would have to
00203 // define all overloads defined in MatrixBase. Furthermore, Using
00204 // "using Base::operator*" would not work with MSVC.
00205 //
00206 // Also note that here we accept any compatible scalar types
00207 template<typename Derived,typename Lhs,typename Rhs>
00208 const ScaledProduct<Derived>
00209 operator*(const ProductBase<Derived,Lhs,Rhs>& prod, typename Derived::Scalar x)
00210 { return ScaledProduct<Derived>(prod.derived(), x); }
00211 
00212 template<typename Derived,typename Lhs,typename Rhs>
00213 typename internal::enable_if<!internal::is_same<typename Derived::Scalar,typename Derived::RealScalar>::value,
00214                       const ScaledProduct<Derived> >::type
00215 operator*(const ProductBase<Derived,Lhs,Rhs>& prod, typename Derived::RealScalar x)
00216 { return ScaledProduct<Derived>(prod.derived(), x); }
00217 
00218 
00219 template<typename Derived,typename Lhs,typename Rhs>
00220 const ScaledProduct<Derived>
00221 operator*(typename Derived::Scalar x,const ProductBase<Derived,Lhs,Rhs>& prod)
00222 { return ScaledProduct<Derived>(prod.derived(), x); }
00223 
00224 template<typename Derived,typename Lhs,typename Rhs>
00225 typename internal::enable_if<!internal::is_same<typename Derived::Scalar,typename Derived::RealScalar>::value,
00226                       const ScaledProduct<Derived> >::type
00227 operator*(typename Derived::RealScalar x,const ProductBase<Derived,Lhs,Rhs>& prod)
00228 { return ScaledProduct<Derived>(prod.derived(), x); }
00229 
00230 namespace internal {
00231 template<typename NestedProduct>
00232 struct traits<ScaledProduct<NestedProduct> >
00233  : traits<ProductBase<ScaledProduct<NestedProduct>,
00234                          typename NestedProduct::_LhsNested,
00235                          typename NestedProduct::_RhsNested> >
00236 {
00237   typedef typename traits<NestedProduct>::StorageKind StorageKind;
00238 };
00239 }
00240 
00241 template<typename NestedProduct>
00242 class ScaledProduct
00243   : public ProductBase<ScaledProduct<NestedProduct>,
00244                        typename NestedProduct::_LhsNested,
00245                        typename NestedProduct::_RhsNested>
00246 {
00247   public:
00248     typedef ProductBase<ScaledProduct<NestedProduct>,
00249                        typename NestedProduct::_LhsNested,
00250                        typename NestedProduct::_RhsNested> Base;
00251     typedef typename Base::Scalar Scalar;
00252     typedef typename Base::PlainObject PlainObject;
00253 //     EIGEN_PRODUCT_PUBLIC_INTERFACE(ScaledProduct)
00254 
00255     ScaledProduct(const NestedProduct& prod, Scalar x)
00256     : Base(prod.lhs(),prod.rhs()), m_prod(prod), m_alpha(x) {}
00257 
00258     template<typename Dest>
00259     inline void evalTo(Dest& dst) const { dst.setZero(); scaleAndAddTo(dst,m_alpha); }
00260 
00261     template<typename Dest>
00262     inline void addTo(Dest& dst) const { scaleAndAddTo(dst,m_alpha); }
00263 
00264     template<typename Dest>
00265     inline void subTo(Dest& dst) const { scaleAndAddTo(dst,-m_alpha); }
00266 
00267     template<typename Dest>
00268     inline void scaleAndAddTo(Dest& dst,Scalar alpha) const { m_prod.derived().scaleAndAddTo(dst,alpha); }
00269 
00270     const Scalar& alpha() const { return m_alpha; }
00271     
00272   protected:
00273     const NestedProduct& m_prod;
00274     Scalar m_alpha;
00275 };
00276 
00279 template<typename Derived>
00280 template<typename ProductDerived, typename Lhs, typename Rhs>
00281 Derived& MatrixBase<Derived>::lazyAssign(const ProductBase<ProductDerived, Lhs,Rhs>& other)
00282 {
00283   other.derived().evalTo(derived());
00284   return derived();
00285 }
00286 
00287 
00288 #endif // EIGEN_PRODUCTBASE_H


libicr
Author(s): Robert Krug
autogenerated on Mon Jan 6 2014 11:33:13