1 // This file is part of Eigen, a lightweight C++ template library 2 // for linear algebra. 3 // 4 // Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr> 5 // Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com> 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_COMMAINITIALIZER_H 12 #define EIGEN_COMMAINITIALIZER_H 13 14 namespace Eigen { 15 16 /** \class CommaInitializer 17 * \ingroup Core_Module 18 * 19 * \brief Helper class used by the comma initializer operator 20 * 21 * This class is internally used to implement the comma initializer feature. It is 22 * the return type of MatrixBase::operator<<, and most of the time this is the only 23 * way it is used. 24 * 25 * \sa \ref MatrixBaseCommaInitRef "MatrixBase::operator<<", CommaInitializer::finished() 26 */ 27 template<typename XprType> 28 struct CommaInitializer 29 { 30 typedef typename XprType::Scalar Scalar; 31 typedef typename XprType::Index Index; 32 CommaInitializerCommaInitializer33 inline CommaInitializer(XprType& xpr, const Scalar& s) 34 : m_xpr(xpr), m_row(0), m_col(1), m_currentBlockRows(1) 35 { 36 m_xpr.coeffRef(0,0) = s; 37 } 38 39 template<typename OtherDerived> CommaInitializerCommaInitializer40 inline CommaInitializer(XprType& xpr, const DenseBase<OtherDerived>& other) 41 : m_xpr(xpr), m_row(0), m_col(other.cols()), m_currentBlockRows(other.rows()) 42 { 43 m_xpr.block(0, 0, other.rows(), other.cols()) = other; 44 } 45 46 /* Copy/Move constructor which transfers ownership. This is crucial in 47 * absence of return value optimization to avoid assertions during destruction. */ 48 // FIXME in C++11 mode this could be replaced by a proper RValue constructor CommaInitializerCommaInitializer49 inline CommaInitializer(const CommaInitializer& o) 50 : m_xpr(o.m_xpr), m_row(o.m_row), m_col(o.m_col), m_currentBlockRows(o.m_currentBlockRows) { 51 // Mark original object as finished. In absence of R-value references we need to const_cast: 52 const_cast<CommaInitializer&>(o).m_row = m_xpr.rows(); 53 const_cast<CommaInitializer&>(o).m_col = m_xpr.cols(); 54 const_cast<CommaInitializer&>(o).m_currentBlockRows = 0; 55 } 56 57 /* inserts a scalar value in the target matrix */ 58 CommaInitializer& operator,(const Scalar& s) 59 { 60 if (m_col==m_xpr.cols()) 61 { 62 m_row+=m_currentBlockRows; 63 m_col = 0; 64 m_currentBlockRows = 1; 65 eigen_assert(m_row<m_xpr.rows() 66 && "Too many rows passed to comma initializer (operator<<)"); 67 } 68 eigen_assert(m_col<m_xpr.cols() 69 && "Too many coefficients passed to comma initializer (operator<<)"); 70 eigen_assert(m_currentBlockRows==1); 71 m_xpr.coeffRef(m_row, m_col++) = s; 72 return *this; 73 } 74 75 /* inserts a matrix expression in the target matrix */ 76 template<typename OtherDerived> 77 CommaInitializer& operator,(const DenseBase<OtherDerived>& other) 78 { 79 if(other.cols()==0 || other.rows()==0) 80 return *this; 81 if (m_col==m_xpr.cols()) 82 { 83 m_row+=m_currentBlockRows; 84 m_col = 0; 85 m_currentBlockRows = other.rows(); 86 eigen_assert(m_row+m_currentBlockRows<=m_xpr.rows() 87 && "Too many rows passed to comma initializer (operator<<)"); 88 } 89 eigen_assert(m_col<m_xpr.cols() 90 && "Too many coefficients passed to comma initializer (operator<<)"); 91 eigen_assert(m_currentBlockRows==other.rows()); 92 if (OtherDerived::SizeAtCompileTime != Dynamic) 93 m_xpr.template block<OtherDerived::RowsAtCompileTime != Dynamic ? OtherDerived::RowsAtCompileTime : 1, 94 OtherDerived::ColsAtCompileTime != Dynamic ? OtherDerived::ColsAtCompileTime : 1> 95 (m_row, m_col) = other; 96 else 97 m_xpr.block(m_row, m_col, other.rows(), other.cols()) = other; 98 m_col += other.cols(); 99 return *this; 100 } 101 ~CommaInitializerCommaInitializer102 inline ~CommaInitializer() 103 { 104 eigen_assert((m_row+m_currentBlockRows) == m_xpr.rows() 105 && m_col == m_xpr.cols() 106 && "Too few coefficients passed to comma initializer (operator<<)"); 107 } 108 109 /** \returns the built matrix once all its coefficients have been set. 110 * Calling finished is 100% optional. Its purpose is to write expressions 111 * like this: 112 * \code 113 * quaternion.fromRotationMatrix((Matrix3f() << axis0, axis1, axis2).finished()); 114 * \endcode 115 */ finishedCommaInitializer116 inline XprType& finished() { return m_xpr; } 117 118 XprType& m_xpr; // target expression 119 Index m_row; // current row id 120 Index m_col; // current col id 121 Index m_currentBlockRows; // current block height 122 }; 123 124 /** \anchor MatrixBaseCommaInitRef 125 * Convenient operator to set the coefficients of a matrix. 126 * 127 * The coefficients must be provided in a row major order and exactly match 128 * the size of the matrix. Otherwise an assertion is raised. 129 * 130 * Example: \include MatrixBase_set.cpp 131 * Output: \verbinclude MatrixBase_set.out 132 * 133 * \note According the c++ standard, the argument expressions of this comma initializer are evaluated in arbitrary order. 134 * 135 * \sa CommaInitializer::finished(), class CommaInitializer 136 */ 137 template<typename Derived> 138 inline CommaInitializer<Derived> DenseBase<Derived>::operator<< (const Scalar& s) 139 { 140 return CommaInitializer<Derived>(*static_cast<Derived*>(this), s); 141 } 142 143 /** \sa operator<<(const Scalar&) */ 144 template<typename Derived> 145 template<typename OtherDerived> 146 inline CommaInitializer<Derived> 147 DenseBase<Derived>::operator<<(const DenseBase<OtherDerived>& other) 148 { 149 return CommaInitializer<Derived>(*static_cast<Derived *>(this), other); 150 } 151 152 } // end namespace Eigen 153 154 #endif // EIGEN_COMMAINITIALIZER_H 155