1 // This file is part of Eigen, a lightweight C++ template library 2 // for linear algebra. 3 // 4 // Copyright (C) 2008 Gael Guennebaud <[email protected]> 5 // Copyright (C) 2006-2008 Benoit Jacob <[email protected]> 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_NESTBYVALUE_H 12 #define EIGEN_NESTBYVALUE_H 13 14 namespace Eigen { 15 16 namespace internal { 17 template<typename ExpressionType> 18 struct traits<NestByValue<ExpressionType> > : public traits<ExpressionType> 19 { 20 enum { 21 Flags = traits<ExpressionType>::Flags & ~NestByRefBit 22 }; 23 }; 24 } 25 26 /** \class NestByValue 27 * \ingroup Core_Module 28 * 29 * \brief Expression which must be nested by value 30 * 31 * \tparam ExpressionType the type of the object of which we are requiring nesting-by-value 32 * 33 * This class is the return type of MatrixBase::nestByValue() 34 * and most of the time this is the only way it is used. 35 * 36 * \sa MatrixBase::nestByValue() 37 */ 38 template<typename ExpressionType> class NestByValue 39 : public internal::dense_xpr_base< NestByValue<ExpressionType> >::type 40 { 41 public: 42 43 typedef typename internal::dense_xpr_base<NestByValue>::type Base; 44 EIGEN_DENSE_PUBLIC_INTERFACE(NestByValue) 45 46 EIGEN_DEVICE_FUNC explicit inline NestByValue(const ExpressionType& matrix) : m_expression(matrix) {} 47 48 EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index rows() const EIGEN_NOEXCEPT { return m_expression.rows(); } 49 EIGEN_DEVICE_FUNC EIGEN_CONSTEXPR inline Index cols() const EIGEN_NOEXCEPT { return m_expression.cols(); } 50 51 EIGEN_DEVICE_FUNC operator const ExpressionType&() const { return m_expression; } 52 53 EIGEN_DEVICE_FUNC const ExpressionType& nestedExpression() const { return m_expression; } 54 55 protected: 56 const ExpressionType m_expression; 57 }; 58 59 /** \returns an expression of the temporary version of *this. 60 */ 61 template<typename Derived> 62 EIGEN_DEVICE_FUNC inline const NestByValue<Derived> 63 DenseBase<Derived>::nestByValue() const 64 { 65 return NestByValue<Derived>(derived()); 66 } 67 68 namespace internal { 69 70 // Evaluator of Solve -> eval into a temporary 71 template<typename ArgType> 72 struct evaluator<NestByValue<ArgType> > 73 : public evaluator<ArgType> 74 { 75 typedef evaluator<ArgType> Base; 76 77 EIGEN_DEVICE_FUNC explicit evaluator(const NestByValue<ArgType>& xpr) 78 : Base(xpr.nestedExpression()) 79 {} 80 }; 81 } 82 83 } // end namespace Eigen 84 85 #endif // EIGEN_NESTBYVALUE_H 86