Narayan Kamath | c981c48 | 2012-11-02 10:59:05 +0000 | [diff] [blame] | 1 | // This file is part of Eigen, a lightweight C++ template library |
| 2 | // for linear algebra. |
| 3 | // |
| 4 | // Copyright (C) 2007-2010 Benoit Jacob <jacob.benoit.1@gmail.com> |
| 5 | // Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr> |
| 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_MAP_H |
| 12 | #define EIGEN_MAP_H |
| 13 | |
| 14 | namespace Eigen { |
| 15 | |
| 16 | /** \class Map |
| 17 | * \ingroup Core_Module |
| 18 | * |
| 19 | * \brief A matrix or vector expression mapping an existing array of data. |
| 20 | * |
| 21 | * \tparam PlainObjectType the equivalent matrix type of the mapped data |
| 22 | * \tparam MapOptions specifies whether the pointer is \c #Aligned, or \c #Unaligned. |
| 23 | * The default is \c #Unaligned. |
| 24 | * \tparam StrideType optionally specifies strides. By default, Map assumes the memory layout |
| 25 | * of an ordinary, contiguous array. This can be overridden by specifying strides. |
| 26 | * The type passed here must be a specialization of the Stride template, see examples below. |
| 27 | * |
| 28 | * This class represents a matrix or vector expression mapping an existing array of data. |
| 29 | * It can be used to let Eigen interface without any overhead with non-Eigen data structures, |
| 30 | * such as plain C arrays or structures from other libraries. By default, it assumes that the |
| 31 | * data is laid out contiguously in memory. You can however override this by explicitly specifying |
| 32 | * inner and outer strides. |
| 33 | * |
| 34 | * Here's an example of simply mapping a contiguous array as a \ref TopicStorageOrders "column-major" matrix: |
| 35 | * \include Map_simple.cpp |
| 36 | * Output: \verbinclude Map_simple.out |
| 37 | * |
| 38 | * If you need to map non-contiguous arrays, you can do so by specifying strides: |
| 39 | * |
| 40 | * Here's an example of mapping an array as a vector, specifying an inner stride, that is, the pointer |
| 41 | * increment between two consecutive coefficients. Here, we're specifying the inner stride as a compile-time |
| 42 | * fixed value. |
| 43 | * \include Map_inner_stride.cpp |
| 44 | * Output: \verbinclude Map_inner_stride.out |
| 45 | * |
| 46 | * Here's an example of mapping an array while specifying an outer stride. Here, since we're mapping |
| 47 | * as a column-major matrix, 'outer stride' means the pointer increment between two consecutive columns. |
| 48 | * Here, we're specifying the outer stride as a runtime parameter. Note that here \c OuterStride<> is |
| 49 | * a short version of \c OuterStride<Dynamic> because the default template parameter of OuterStride |
| 50 | * is \c Dynamic |
| 51 | * \include Map_outer_stride.cpp |
| 52 | * Output: \verbinclude Map_outer_stride.out |
| 53 | * |
| 54 | * For more details and for an example of specifying both an inner and an outer stride, see class Stride. |
| 55 | * |
| 56 | * \b Tip: to change the array of data mapped by a Map object, you can use the C++ |
| 57 | * placement new syntax: |
| 58 | * |
| 59 | * Example: \include Map_placement_new.cpp |
| 60 | * Output: \verbinclude Map_placement_new.out |
| 61 | * |
| 62 | * This class is the return type of PlainObjectBase::Map() but can also be used directly. |
| 63 | * |
| 64 | * \sa PlainObjectBase::Map(), \ref TopicStorageOrders |
| 65 | */ |
| 66 | |
| 67 | namespace internal { |
| 68 | template<typename PlainObjectType, int MapOptions, typename StrideType> |
| 69 | struct traits<Map<PlainObjectType, MapOptions, StrideType> > |
| 70 | : public traits<PlainObjectType> |
| 71 | { |
| 72 | typedef traits<PlainObjectType> TraitsBase; |
| 73 | typedef typename PlainObjectType::Index Index; |
| 74 | typedef typename PlainObjectType::Scalar Scalar; |
| 75 | enum { |
| 76 | InnerStrideAtCompileTime = StrideType::InnerStrideAtCompileTime == 0 |
| 77 | ? int(PlainObjectType::InnerStrideAtCompileTime) |
| 78 | : int(StrideType::InnerStrideAtCompileTime), |
| 79 | OuterStrideAtCompileTime = StrideType::OuterStrideAtCompileTime == 0 |
| 80 | ? int(PlainObjectType::OuterStrideAtCompileTime) |
| 81 | : int(StrideType::OuterStrideAtCompileTime), |
| 82 | HasNoInnerStride = InnerStrideAtCompileTime == 1, |
| 83 | HasNoOuterStride = StrideType::OuterStrideAtCompileTime == 0, |
| 84 | HasNoStride = HasNoInnerStride && HasNoOuterStride, |
| 85 | IsAligned = bool(EIGEN_ALIGN) && ((int(MapOptions)&Aligned)==Aligned), |
| 86 | IsDynamicSize = PlainObjectType::SizeAtCompileTime==Dynamic, |
| 87 | KeepsPacketAccess = bool(HasNoInnerStride) |
| 88 | && ( bool(IsDynamicSize) |
| 89 | || HasNoOuterStride |
| 90 | || ( OuterStrideAtCompileTime!=Dynamic |
| 91 | && ((static_cast<int>(sizeof(Scalar))*OuterStrideAtCompileTime)%16)==0 ) ), |
| 92 | Flags0 = TraitsBase::Flags & (~NestByRefBit), |
| 93 | Flags1 = IsAligned ? (int(Flags0) | AlignedBit) : (int(Flags0) & ~AlignedBit), |
| 94 | Flags2 = (bool(HasNoStride) || bool(PlainObjectType::IsVectorAtCompileTime)) |
| 95 | ? int(Flags1) : int(Flags1 & ~LinearAccessBit), |
| 96 | Flags3 = is_lvalue<PlainObjectType>::value ? int(Flags2) : (int(Flags2) & ~LvalueBit), |
| 97 | Flags = KeepsPacketAccess ? int(Flags3) : (int(Flags3) & ~PacketAccessBit) |
| 98 | }; |
| 99 | private: |
| 100 | enum { Options }; // Expressions don't have Options |
| 101 | }; |
| 102 | } |
| 103 | |
| 104 | template<typename PlainObjectType, int MapOptions, typename StrideType> class Map |
| 105 | : public MapBase<Map<PlainObjectType, MapOptions, StrideType> > |
| 106 | { |
| 107 | public: |
| 108 | |
| 109 | typedef MapBase<Map> Base; |
| 110 | EIGEN_DENSE_PUBLIC_INTERFACE(Map) |
| 111 | |
| 112 | typedef typename Base::PointerType PointerType; |
| 113 | #if EIGEN2_SUPPORT_STAGE <= STAGE30_FULL_EIGEN3_API |
| 114 | typedef const Scalar* PointerArgType; |
| 115 | inline PointerType cast_to_pointer_type(PointerArgType ptr) { return const_cast<PointerType>(ptr); } |
| 116 | #else |
| 117 | typedef PointerType PointerArgType; |
| 118 | inline PointerType cast_to_pointer_type(PointerArgType ptr) { return ptr; } |
| 119 | #endif |
| 120 | |
| 121 | inline Index innerStride() const |
| 122 | { |
| 123 | return StrideType::InnerStrideAtCompileTime != 0 ? m_stride.inner() : 1; |
| 124 | } |
| 125 | |
| 126 | inline Index outerStride() const |
| 127 | { |
| 128 | return StrideType::OuterStrideAtCompileTime != 0 ? m_stride.outer() |
| 129 | : IsVectorAtCompileTime ? this->size() |
| 130 | : int(Flags)&RowMajorBit ? this->cols() |
| 131 | : this->rows(); |
| 132 | } |
| 133 | |
| 134 | /** Constructor in the fixed-size case. |
| 135 | * |
Carlos Hernandez | 7faaa9f | 2014-08-05 17:53:32 -0700 | [diff] [blame] | 136 | * \param dataPtr pointer to the array to map |
| 137 | * \param a_stride optional Stride object, passing the strides. |
Narayan Kamath | c981c48 | 2012-11-02 10:59:05 +0000 | [diff] [blame] | 138 | */ |
Carlos Hernandez | 7faaa9f | 2014-08-05 17:53:32 -0700 | [diff] [blame] | 139 | inline Map(PointerArgType dataPtr, const StrideType& a_stride = StrideType()) |
| 140 | : Base(cast_to_pointer_type(dataPtr)), m_stride(a_stride) |
Narayan Kamath | c981c48 | 2012-11-02 10:59:05 +0000 | [diff] [blame] | 141 | { |
| 142 | PlainObjectType::Base::_check_template_params(); |
| 143 | } |
| 144 | |
| 145 | /** Constructor in the dynamic-size vector case. |
| 146 | * |
Carlos Hernandez | 7faaa9f | 2014-08-05 17:53:32 -0700 | [diff] [blame] | 147 | * \param dataPtr pointer to the array to map |
| 148 | * \param a_size the size of the vector expression |
| 149 | * \param a_stride optional Stride object, passing the strides. |
Narayan Kamath | c981c48 | 2012-11-02 10:59:05 +0000 | [diff] [blame] | 150 | */ |
Carlos Hernandez | 7faaa9f | 2014-08-05 17:53:32 -0700 | [diff] [blame] | 151 | inline Map(PointerArgType dataPtr, Index a_size, const StrideType& a_stride = StrideType()) |
| 152 | : Base(cast_to_pointer_type(dataPtr), a_size), m_stride(a_stride) |
Narayan Kamath | c981c48 | 2012-11-02 10:59:05 +0000 | [diff] [blame] | 153 | { |
| 154 | PlainObjectType::Base::_check_template_params(); |
| 155 | } |
| 156 | |
| 157 | /** Constructor in the dynamic-size matrix case. |
| 158 | * |
Carlos Hernandez | 7faaa9f | 2014-08-05 17:53:32 -0700 | [diff] [blame] | 159 | * \param dataPtr pointer to the array to map |
| 160 | * \param nbRows the number of rows of the matrix expression |
| 161 | * \param nbCols the number of columns of the matrix expression |
| 162 | * \param a_stride optional Stride object, passing the strides. |
Narayan Kamath | c981c48 | 2012-11-02 10:59:05 +0000 | [diff] [blame] | 163 | */ |
Carlos Hernandez | 7faaa9f | 2014-08-05 17:53:32 -0700 | [diff] [blame] | 164 | inline Map(PointerArgType dataPtr, Index nbRows, Index nbCols, const StrideType& a_stride = StrideType()) |
| 165 | : Base(cast_to_pointer_type(dataPtr), nbRows, nbCols), m_stride(a_stride) |
Narayan Kamath | c981c48 | 2012-11-02 10:59:05 +0000 | [diff] [blame] | 166 | { |
| 167 | PlainObjectType::Base::_check_template_params(); |
| 168 | } |
| 169 | |
| 170 | EIGEN_INHERIT_ASSIGNMENT_OPERATORS(Map) |
| 171 | |
| 172 | protected: |
| 173 | StrideType m_stride; |
| 174 | }; |
| 175 | |
| 176 | template<typename _Scalar, int _Rows, int _Cols, int _Options, int _MaxRows, int _MaxCols> |
| 177 | inline Array<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols> |
| 178 | ::Array(const Scalar *data) |
| 179 | { |
| 180 | this->_set_noalias(Eigen::Map<const Array>(data)); |
| 181 | } |
| 182 | |
| 183 | template<typename _Scalar, int _Rows, int _Cols, int _Options, int _MaxRows, int _MaxCols> |
| 184 | inline Matrix<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols> |
| 185 | ::Matrix(const Scalar *data) |
| 186 | { |
| 187 | this->_set_noalias(Eigen::Map<const Matrix>(data)); |
| 188 | } |
| 189 | |
| 190 | } // end namespace Eigen |
| 191 | |
| 192 | #endif // EIGEN_MAP_H |