1 // This file is part of Eigen, a lightweight C++ template library 2 // for linear algebra. 3 // 4 // Copyright (C) 2008-2009 Gael Guennebaud <gael.guennebaud (at) inria.fr> 5 // Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1 (at) 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_BLOCK2_H 12 #define EIGEN_BLOCK2_H 13 14 namespace Eigen { 15 16 /** \returns a dynamic-size expression of a corner of *this. 17 * 18 * \param type the type of corner. Can be \a Eigen::TopLeft, \a Eigen::TopRight, 19 * \a Eigen::BottomLeft, \a Eigen::BottomRight. 20 * \param cRows the number of rows in the corner 21 * \param cCols the number of columns in the corner 22 * 23 * Example: \include MatrixBase_corner_enum_int_int.cpp 24 * Output: \verbinclude MatrixBase_corner_enum_int_int.out 25 * 26 * \note Even though the returned expression has dynamic size, in the case 27 * when it is applied to a fixed-size matrix, it inherits a fixed maximal size, 28 * which means that evaluating it does not cause a dynamic memory allocation. 29 * 30 * \sa class Block, block(Index,Index,Index,Index) 31 */ 32 template<typename Derived> 33 inline Block<Derived> DenseBase<Derived> 34 ::corner(CornerType type, Index cRows, Index cCols) 35 { 36 switch(type) 37 { 38 default: 39 eigen_assert(false && "Bad corner type."); 40 case TopLeft: 41 return Block<Derived>(derived(), 0, 0, cRows, cCols); 42 case TopRight: 43 return Block<Derived>(derived(), 0, cols() - cCols, cRows, cCols); 44 case BottomLeft: 45 return Block<Derived>(derived(), rows() - cRows, 0, cRows, cCols); 46 case BottomRight: 47 return Block<Derived>(derived(), rows() - cRows, cols() - cCols, cRows, cCols); 48 } 49 } 50 51 /** This is the const version of corner(CornerType, Index, Index).*/ 52 template<typename Derived> 53 inline const Block<Derived> 54 DenseBase<Derived>::corner(CornerType type, Index cRows, Index cCols) const 55 { 56 switch(type) 57 { 58 default: 59 eigen_assert(false && "Bad corner type."); 60 case TopLeft: 61 return Block<Derived>(derived(), 0, 0, cRows, cCols); 62 case TopRight: 63 return Block<Derived>(derived(), 0, cols() - cCols, cRows, cCols); 64 case BottomLeft: 65 return Block<Derived>(derived(), rows() - cRows, 0, cRows, cCols); 66 case BottomRight: 67 return Block<Derived>(derived(), rows() - cRows, cols() - cCols, cRows, cCols); 68 } 69 } 70 71 /** \returns a fixed-size expression of a corner of *this. 72 * 73 * \param type the type of corner. Can be \a Eigen::TopLeft, \a Eigen::TopRight, 74 * \a Eigen::BottomLeft, \a Eigen::BottomRight. 75 * 76 * The template parameters CRows and CCols arethe number of rows and columns in the corner. 77 * 78 * Example: \include MatrixBase_template_int_int_corner_enum.cpp 79 * Output: \verbinclude MatrixBase_template_int_int_corner_enum.out 80 * 81 * \sa class Block, block(Index,Index,Index,Index) 82 */ 83 template<typename Derived> 84 template<int CRows, int CCols> 85 inline Block<Derived, CRows, CCols> 86 DenseBase<Derived>::corner(CornerType type) 87 { 88 switch(type) 89 { 90 default: 91 eigen_assert(false && "Bad corner type."); 92 case TopLeft: 93 return Block<Derived, CRows, CCols>(derived(), 0, 0); 94 case TopRight: 95 return Block<Derived, CRows, CCols>(derived(), 0, cols() - CCols); 96 case BottomLeft: 97 return Block<Derived, CRows, CCols>(derived(), rows() - CRows, 0); 98 case BottomRight: 99 return Block<Derived, CRows, CCols>(derived(), rows() - CRows, cols() - CCols); 100 } 101 } 102 103 /** This is the const version of corner<int, int>(CornerType).*/ 104 template<typename Derived> 105 template<int CRows, int CCols> 106 inline const Block<Derived, CRows, CCols> 107 DenseBase<Derived>::corner(CornerType type) const 108 { 109 switch(type) 110 { 111 default: 112 eigen_assert(false && "Bad corner type."); 113 case TopLeft: 114 return Block<Derived, CRows, CCols>(derived(), 0, 0); 115 case TopRight: 116 return Block<Derived, CRows, CCols>(derived(), 0, cols() - CCols); 117 case BottomLeft: 118 return Block<Derived, CRows, CCols>(derived(), rows() - CRows, 0); 119 case BottomRight: 120 return Block<Derived, CRows, CCols>(derived(), rows() - CRows, cols() - CCols); 121 } 122 } 123 124 } // end namespace Eigen 125 126 #endif // EIGEN_BLOCK2_H 127
