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 \blank \ref MatrixBaseCommaInitRef "MatrixBase::operator<<", CommaInitializer::finished() 26 */ 27 template<typename XprType> 28 struct CommaInitializer 29 { 30 typedef typename XprType::Scalar Scalar; 31 32 EIGEN_DEVICE_FUNC 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> 40 EIGEN_DEVICE_FUNC CommaInitializerCommaInitializer41 inline CommaInitializer(XprType& xpr, const DenseBase<OtherDerived>& other) 42 : m_xpr(xpr), m_row(0), m_col(other.cols()), m_currentBlockRows(other.rows()) 43 { 44 m_xpr.block(0, 0, other.rows(), other.cols()) = other; 45 } 46 47 /* Copy/Move constructor which transfers ownership. This is crucial in 48 * absence of return value optimization to avoid assertions during destruction. */ 49 // FIXME in C++11 mode this could be replaced by a proper RValue constructor 50 EIGEN_DEVICE_FUNC CommaInitializerCommaInitializer51 inline CommaInitializer(const CommaInitializer& o) 52 : m_xpr(o.m_xpr), m_row(o.m_row), m_col(o.m_col), m_currentBlockRows(o.m_currentBlockRows) { 53 // Mark original object as finished. In absence of R-value references we need to const_cast: 54 const_cast<CommaInitializer&>(o).m_row = m_xpr.rows(); 55 const_cast<CommaInitializer&>(o).m_col = m_xpr.cols(); 56 const_cast<CommaInitializer&>(o).m_currentBlockRows = 0; 57 } 58 59 /* inserts a scalar value in the target matrix */ 60 EIGEN_DEVICE_FUNC 61 CommaInitializer& operator,(const Scalar& s) 62 { 63 if (m_col==m_xpr.cols()) 64 { 65 m_row+=m_currentBlockRows; 66 m_col = 0; 67 m_currentBlockRows = 1; 68 eigen_assert(m_row<m_xpr.rows() 69 && "Too many rows passed to comma initializer (operator<<)"); 70 } 71 eigen_assert(m_col<m_xpr.cols() 72 && "Too many coefficients passed to comma initializer (operator<<)"); 73 eigen_assert(m_currentBlockRows==1); 74 m_xpr.coeffRef(m_row, m_col++) = s; 75 return *this; 76 } 77 78 /* inserts a matrix expression in the target matrix */ 79 template<typename OtherDerived> 80 EIGEN_DEVICE_FUNC 81 CommaInitializer& operator,(const DenseBase<OtherDerived>& other) 82 { 83 if (m_col==m_xpr.cols() && (other.cols()!=0 || other.rows()!=m_currentBlockRows)) 84 { 85 m_row+=m_currentBlockRows; 86 m_col = 0; 87 m_currentBlockRows = other.rows(); 88 eigen_assert(m_row+m_currentBlockRows<=m_xpr.rows() 89 && "Too many rows passed to comma initializer (operator<<)"); 90 } 91 eigen_assert((m_col + other.cols() <= m_xpr.cols()) 92 && "Too many coefficients passed to comma initializer (operator<<)"); 93 eigen_assert(m_currentBlockRows==other.rows()); 94 m_xpr.template block<OtherDerived::RowsAtCompileTime, OtherDerived::ColsAtCompileTime> 95 (m_row, m_col, other.rows(), other.cols()) = other; 96 m_col += other.cols(); 97 return *this; 98 } 99 100 EIGEN_DEVICE_FUNC ~CommaInitializerCommaInitializer101 inline ~CommaInitializer() 102 #if defined VERIFY_RAISES_ASSERT && (!defined EIGEN_NO_ASSERTION_CHECKING) && defined EIGEN_EXCEPTIONS 103 EIGEN_EXCEPTION_SPEC(Eigen::eigen_assert_exception) 104 #endif 105 { 106 finished(); 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 */ 116 EIGEN_DEVICE_FUNC finishedCommaInitializer117 inline XprType& finished() { 118 eigen_assert(((m_row+m_currentBlockRows) == m_xpr.rows() || m_xpr.cols() == 0) 119 && m_col == m_xpr.cols() 120 && "Too few coefficients passed to comma initializer (operator<<)"); 121 return m_xpr; 122 } 123 124 XprType& m_xpr; // target expression 125 Index m_row; // current row id 126 Index m_col; // current col id 127 Index m_currentBlockRows; // current block height 128 }; 129 130 /** \anchor MatrixBaseCommaInitRef 131 * Convenient operator to set the coefficients of a matrix. 132 * 133 * The coefficients must be provided in a row major order and exactly match 134 * the size of the matrix. Otherwise an assertion is raised. 135 * 136 * Example: \include MatrixBase_set.cpp 137 * Output: \verbinclude MatrixBase_set.out 138 * 139 * \note According the c++ standard, the argument expressions of this comma initializer are evaluated in arbitrary order. 140 * 141 * \sa CommaInitializer::finished(), class CommaInitializer 142 */ 143 template<typename Derived> 144 inline CommaInitializer<Derived> DenseBase<Derived>::operator<< (const Scalar& s) 145 { 146 return CommaInitializer<Derived>(*static_cast<Derived*>(this), s); 147 } 148 149 /** \sa operator<<(const Scalar&) */ 150 template<typename Derived> 151 template<typename OtherDerived> 152 inline CommaInitializer<Derived> 153 DenseBase<Derived>::operator<<(const DenseBase<OtherDerived>& other) 154 { 155 return CommaInitializer<Derived>(*static_cast<Derived *>(this), other); 156 } 157 158 } // end namespace Eigen 159 160 #endif // EIGEN_COMMAINITIALIZER_H 161