Home | History | Annotate | Download | only in Core
      1 // This file is part of Eigen, a lightweight C++ template library
      2 // for linear algebra.
      3 //
      4 // Copyright (C) 2006-2010 Benoit Jacob <jacob.benoit.1 (at) gmail.com>
      5 // Copyright (C) 2008-2009 Gael Guennebaud <gael.guennebaud (at) 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_MATRIX_H
     12 #define EIGEN_MATRIX_H
     13 
     14 namespace Eigen {
     15 
     16 /** \class Matrix
     17   * \ingroup Core_Module
     18   *
     19   * \brief The matrix class, also used for vectors and row-vectors
     20   *
     21   * The %Matrix class is the work-horse for all \em dense (\ref dense "note") matrices and vectors within Eigen.
     22   * Vectors are matrices with one column, and row-vectors are matrices with one row.
     23   *
     24   * The %Matrix class encompasses \em both fixed-size and dynamic-size objects (\ref fixedsize "note").
     25   *
     26   * The first three template parameters are required:
     27   * \tparam _Scalar \anchor matrix_tparam_scalar Numeric type, e.g. float, double, int or std::complex<float>.
     28   *                 User defined sclar types are supported as well (see \ref user_defined_scalars "here").
     29   * \tparam _Rows Number of rows, or \b Dynamic
     30   * \tparam _Cols Number of columns, or \b Dynamic
     31   *
     32   * The remaining template parameters are optional -- in most cases you don't have to worry about them.
     33   * \tparam _Options \anchor matrix_tparam_options A combination of either \b #RowMajor or \b #ColMajor, and of either
     34   *                 \b #AutoAlign or \b #DontAlign.
     35   *                 The former controls \ref TopicStorageOrders "storage order", and defaults to column-major. The latter controls alignment, which is required
     36   *                 for vectorization. It defaults to aligning matrices except for fixed sizes that aren't a multiple of the packet size.
     37   * \tparam _MaxRows Maximum number of rows. Defaults to \a _Rows (\ref maxrows "note").
     38   * \tparam _MaxCols Maximum number of columns. Defaults to \a _Cols (\ref maxrows "note").
     39   *
     40   * Eigen provides a number of typedefs covering the usual cases. Here are some examples:
     41   *
     42   * \li \c Matrix2d is a 2x2 square matrix of doubles (\c Matrix<double, 2, 2>)
     43   * \li \c Vector4f is a vector of 4 floats (\c Matrix<float, 4, 1>)
     44   * \li \c RowVector3i is a row-vector of 3 ints (\c Matrix<int, 1, 3>)
     45   *
     46   * \li \c MatrixXf is a dynamic-size matrix of floats (\c Matrix<float, Dynamic, Dynamic>)
     47   * \li \c VectorXf is a dynamic-size vector of floats (\c Matrix<float, Dynamic, 1>)
     48   *
     49   * \li \c Matrix2Xf is a partially fixed-size (dynamic-size) matrix of floats (\c Matrix<float, 2, Dynamic>)
     50   * \li \c MatrixX3d is a partially dynamic-size (fixed-size) matrix of double (\c Matrix<double, Dynamic, 3>)
     51   *
     52   * See \link matrixtypedefs this page \endlink for a complete list of predefined \em %Matrix and \em Vector typedefs.
     53   *
     54   * You can access elements of vectors and matrices using normal subscripting:
     55   *
     56   * \code
     57   * Eigen::VectorXd v(10);
     58   * v[0] = 0.1;
     59   * v[1] = 0.2;
     60   * v(0) = 0.3;
     61   * v(1) = 0.4;
     62   *
     63   * Eigen::MatrixXi m(10, 10);
     64   * m(0, 1) = 1;
     65   * m(0, 2) = 2;
     66   * m(0, 3) = 3;
     67   * \endcode
     68   *
     69   * This class can be extended with the help of the plugin mechanism described on the page
     70   * \ref TopicCustomizingEigen by defining the preprocessor symbol \c EIGEN_MATRIX_PLUGIN.
     71   *
     72   * <i><b>Some notes:</b></i>
     73   *
     74   * <dl>
     75   * <dt><b>\anchor dense Dense versus sparse:</b></dt>
     76   * <dd>This %Matrix class handles dense, not sparse matrices and vectors. For sparse matrices and vectors, see the Sparse module.
     77   *
     78   * Dense matrices and vectors are plain usual arrays of coefficients. All the coefficients are stored, in an ordinary contiguous array.
     79   * This is unlike Sparse matrices and vectors where the coefficients are stored as a list of nonzero coefficients.</dd>
     80   *
     81   * <dt><b>\anchor fixedsize Fixed-size versus dynamic-size:</b></dt>
     82   * <dd>Fixed-size means that the numbers of rows and columns are known are compile-time. In this case, Eigen allocates the array
     83   * of coefficients as a fixed-size array, as a class member. This makes sense for very small matrices, typically up to 4x4, sometimes up
     84   * to 16x16. Larger matrices should be declared as dynamic-size even if one happens to know their size at compile-time.
     85   *
     86   * Dynamic-size means that the numbers of rows or columns are not necessarily known at compile-time. In this case they are runtime
     87   * variables, and the array of coefficients is allocated dynamically on the heap.
     88   *
     89   * Note that \em dense matrices, be they Fixed-size or Dynamic-size, <em>do not</em> expand dynamically in the sense of a std::map.
     90   * If you want this behavior, see the Sparse module.</dd>
     91   *
     92   * <dt><b>\anchor maxrows _MaxRows and _MaxCols:</b></dt>
     93   * <dd>In most cases, one just leaves these parameters to the default values.
     94   * These parameters mean the maximum size of rows and columns that the matrix may have. They are useful in cases
     95   * when the exact numbers of rows and columns are not known are compile-time, but it is known at compile-time that they cannot
     96   * exceed a certain value. This happens when taking dynamic-size blocks inside fixed-size matrices: in this case _MaxRows and _MaxCols
     97   * are the dimensions of the original matrix, while _Rows and _Cols are Dynamic.</dd>
     98   * </dl>
     99   *
    100   * \see MatrixBase for the majority of the API methods for matrices, \ref TopicClassHierarchy,
    101   * \ref TopicStorageOrders
    102   */
    103 
    104 namespace internal {
    105 template<typename _Scalar, int _Rows, int _Cols, int _Options, int _MaxRows, int _MaxCols>
    106 struct traits<Matrix<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols> >
    107 {
    108   typedef _Scalar Scalar;
    109   typedef Dense StorageKind;
    110   typedef DenseIndex Index;
    111   typedef MatrixXpr XprKind;
    112   enum {
    113     RowsAtCompileTime = _Rows,
    114     ColsAtCompileTime = _Cols,
    115     MaxRowsAtCompileTime = _MaxRows,
    116     MaxColsAtCompileTime = _MaxCols,
    117     Flags = compute_matrix_flags<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols>::ret,
    118     CoeffReadCost = NumTraits<Scalar>::ReadCost,
    119     Options = _Options,
    120     InnerStrideAtCompileTime = 1,
    121     OuterStrideAtCompileTime = (Options&RowMajor) ? ColsAtCompileTime : RowsAtCompileTime
    122   };
    123 };
    124 }
    125 
    126 template<typename _Scalar, int _Rows, int _Cols, int _Options, int _MaxRows, int _MaxCols>
    127 class Matrix
    128   : public PlainObjectBase<Matrix<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols> >
    129 {
    130   public:
    131 
    132     /** \brief Base class typedef.
    133       * \sa PlainObjectBase
    134       */
    135     typedef PlainObjectBase<Matrix> Base;
    136 
    137     enum { Options = _Options };
    138 
    139     EIGEN_DENSE_PUBLIC_INTERFACE(Matrix)
    140 
    141     typedef typename Base::PlainObject PlainObject;
    142 
    143     using Base::base;
    144     using Base::coeffRef;
    145 
    146     /**
    147       * \brief Assigns matrices to each other.
    148       *
    149       * \note This is a special case of the templated operator=. Its purpose is
    150       * to prevent a default operator= from hiding the templated operator=.
    151       *
    152       * \callgraph
    153       */
    154     EIGEN_STRONG_INLINE Matrix& operator=(const Matrix& other)
    155     {
    156       return Base::_set(other);
    157     }
    158 
    159     /** \internal
    160       * \brief Copies the value of the expression \a other into \c *this with automatic resizing.
    161       *
    162       * *this might be resized to match the dimensions of \a other. If *this was a null matrix (not already initialized),
    163       * it will be initialized.
    164       *
    165       * Note that copying a row-vector into a vector (and conversely) is allowed.
    166       * The resizing, if any, is then done in the appropriate way so that row-vectors
    167       * remain row-vectors and vectors remain vectors.
    168       */
    169     template<typename OtherDerived>
    170     EIGEN_STRONG_INLINE Matrix& operator=(const MatrixBase<OtherDerived>& other)
    171     {
    172       return Base::_set(other);
    173     }
    174 
    175     /* Here, doxygen failed to copy the brief information when using \copydoc */
    176 
    177     /**
    178       * \brief Copies the generic expression \a other into *this.
    179       * \copydetails DenseBase::operator=(const EigenBase<OtherDerived> &other)
    180       */
    181     template<typename OtherDerived>
    182     EIGEN_STRONG_INLINE Matrix& operator=(const EigenBase<OtherDerived> &other)
    183     {
    184       return Base::operator=(other);
    185     }
    186 
    187     template<typename OtherDerived>
    188     EIGEN_STRONG_INLINE Matrix& operator=(const ReturnByValue<OtherDerived>& func)
    189     {
    190       return Base::operator=(func);
    191     }
    192 
    193     /** \brief Default constructor.
    194       *
    195       * For fixed-size matrices, does nothing.
    196       *
    197       * For dynamic-size matrices, creates an empty matrix of size 0. Does not allocate any array. Such a matrix
    198       * is called a null matrix. This constructor is the unique way to create null matrices: resizing
    199       * a matrix to 0 is not supported.
    200       *
    201       * \sa resize(Index,Index)
    202       */
    203     EIGEN_STRONG_INLINE Matrix() : Base()
    204     {
    205       Base::_check_template_params();
    206       EIGEN_INITIALIZE_COEFFS_IF_THAT_OPTION_IS_ENABLED
    207     }
    208 
    209     // FIXME is it still needed
    210     Matrix(internal::constructor_without_unaligned_array_assert)
    211       : Base(internal::constructor_without_unaligned_array_assert())
    212     { Base::_check_template_params(); EIGEN_INITIALIZE_COEFFS_IF_THAT_OPTION_IS_ENABLED }
    213 
    214     /** \brief Constructs a vector or row-vector with given dimension. \only_for_vectors
    215       *
    216       * Note that this is only useful for dynamic-size vectors. For fixed-size vectors,
    217       * it is redundant to pass the dimension here, so it makes more sense to use the default
    218       * constructor Matrix() instead.
    219       */
    220     EIGEN_STRONG_INLINE explicit Matrix(Index dim)
    221       : Base(dim, RowsAtCompileTime == 1 ? 1 : dim, ColsAtCompileTime == 1 ? 1 : dim)
    222     {
    223       Base::_check_template_params();
    224       EIGEN_STATIC_ASSERT_VECTOR_ONLY(Matrix)
    225       eigen_assert(dim >= 0);
    226       eigen_assert(SizeAtCompileTime == Dynamic || SizeAtCompileTime == dim);
    227       EIGEN_INITIALIZE_COEFFS_IF_THAT_OPTION_IS_ENABLED
    228     }
    229 
    230     #ifndef EIGEN_PARSED_BY_DOXYGEN
    231     template<typename T0, typename T1>
    232     EIGEN_STRONG_INLINE Matrix(const T0& x, const T1& y)
    233     {
    234       Base::_check_template_params();
    235       Base::template _init2<T0,T1>(x, y);
    236     }
    237     #else
    238     /** \brief Constructs an uninitialized matrix with \a rows rows and \a cols columns.
    239       *
    240       * This is useful for dynamic-size matrices. For fixed-size matrices,
    241       * it is redundant to pass these parameters, so one should use the default constructor
    242       * Matrix() instead. */
    243     Matrix(Index rows, Index cols);
    244     /** \brief Constructs an initialized 2D vector with given coefficients */
    245     Matrix(const Scalar& x, const Scalar& y);
    246     #endif
    247 
    248     /** \brief Constructs an initialized 3D vector with given coefficients */
    249     EIGEN_STRONG_INLINE Matrix(const Scalar& x, const Scalar& y, const Scalar& z)
    250     {
    251       Base::_check_template_params();
    252       EIGEN_STATIC_ASSERT_VECTOR_SPECIFIC_SIZE(Matrix, 3)
    253       m_storage.data()[0] = x;
    254       m_storage.data()[1] = y;
    255       m_storage.data()[2] = z;
    256     }
    257     /** \brief Constructs an initialized 4D vector with given coefficients */
    258     EIGEN_STRONG_INLINE Matrix(const Scalar& x, const Scalar& y, const Scalar& z, const Scalar& w)
    259     {
    260       Base::_check_template_params();
    261       EIGEN_STATIC_ASSERT_VECTOR_SPECIFIC_SIZE(Matrix, 4)
    262       m_storage.data()[0] = x;
    263       m_storage.data()[1] = y;
    264       m_storage.data()[2] = z;
    265       m_storage.data()[3] = w;
    266     }
    267 
    268     explicit Matrix(const Scalar *data);
    269 
    270     /** \brief Constructor copying the value of the expression \a other */
    271     template<typename OtherDerived>
    272     EIGEN_STRONG_INLINE Matrix(const MatrixBase<OtherDerived>& other)
    273              : Base(other.rows() * other.cols(), other.rows(), other.cols())
    274     {
    275       // This test resides here, to bring the error messages closer to the user. Normally, these checks
    276       // are performed deeply within the library, thus causing long and scary error traces.
    277       EIGEN_STATIC_ASSERT((internal::is_same<Scalar, typename OtherDerived::Scalar>::value),
    278         YOU_MIXED_DIFFERENT_NUMERIC_TYPES__YOU_NEED_TO_USE_THE_CAST_METHOD_OF_MATRIXBASE_TO_CAST_NUMERIC_TYPES_EXPLICITLY)
    279 
    280       Base::_check_template_params();
    281       Base::_set_noalias(other);
    282     }
    283     /** \brief Copy constructor */
    284     EIGEN_STRONG_INLINE Matrix(const Matrix& other)
    285             : Base(other.rows() * other.cols(), other.rows(), other.cols())
    286     {
    287       Base::_check_template_params();
    288       Base::_set_noalias(other);
    289     }
    290     /** \brief Copy constructor with in-place evaluation */
    291     template<typename OtherDerived>
    292     EIGEN_STRONG_INLINE Matrix(const ReturnByValue<OtherDerived>& other)
    293     {
    294       Base::_check_template_params();
    295       Base::resize(other.rows(), other.cols());
    296       other.evalTo(*this);
    297     }
    298 
    299     /** \brief Copy constructor for generic expressions.
    300       * \sa MatrixBase::operator=(const EigenBase<OtherDerived>&)
    301       */
    302     template<typename OtherDerived>
    303     EIGEN_STRONG_INLINE Matrix(const EigenBase<OtherDerived> &other)
    304       : Base(other.derived().rows() * other.derived().cols(), other.derived().rows(), other.derived().cols())
    305     {
    306       Base::_check_template_params();
    307       Base::_resize_to_match(other);
    308       // FIXME/CHECK: isn't *this = other.derived() more efficient. it allows to
    309       //              go for pure _set() implementations, right?
    310       *this = other;
    311     }
    312 
    313     /** \internal
    314       * \brief Override MatrixBase::swap() since for dynamic-sized matrices
    315       * of same type it is enough to swap the data pointers.
    316       */
    317     template<typename OtherDerived>
    318     void swap(MatrixBase<OtherDerived> const & other)
    319     { this->_swap(other.derived()); }
    320 
    321     inline Index innerStride() const { return 1; }
    322     inline Index outerStride() const { return this->innerSize(); }
    323 
    324     /////////// Geometry module ///////////
    325 
    326     template<typename OtherDerived>
    327     explicit Matrix(const RotationBase<OtherDerived,ColsAtCompileTime>& r);
    328     template<typename OtherDerived>
    329     Matrix& operator=(const RotationBase<OtherDerived,ColsAtCompileTime>& r);
    330 
    331     #ifdef EIGEN2_SUPPORT
    332     template<typename OtherDerived>
    333     explicit Matrix(const eigen2_RotationBase<OtherDerived,ColsAtCompileTime>& r);
    334     template<typename OtherDerived>
    335     Matrix& operator=(const eigen2_RotationBase<OtherDerived,ColsAtCompileTime>& r);
    336     #endif
    337 
    338     // allow to extend Matrix outside Eigen
    339     #ifdef EIGEN_MATRIX_PLUGIN
    340     #include EIGEN_MATRIX_PLUGIN
    341     #endif
    342 
    343   protected:
    344     template <typename Derived, typename OtherDerived, bool IsVector>
    345     friend struct internal::conservative_resize_like_impl;
    346 
    347     using Base::m_storage;
    348 };
    349 
    350 /** \defgroup matrixtypedefs Global matrix typedefs
    351   *
    352   * \ingroup Core_Module
    353   *
    354   * Eigen defines several typedef shortcuts for most common matrix and vector types.
    355   *
    356   * The general patterns are the following:
    357   *
    358   * \c MatrixSizeType where \c Size can be \c 2,\c 3,\c 4 for fixed size square matrices or \c X for dynamic size,
    359   * and where \c Type can be \c i for integer, \c f for float, \c d for double, \c cf for complex float, \c cd
    360   * for complex double.
    361   *
    362   * For example, \c Matrix3d is a fixed-size 3x3 matrix type of doubles, and \c MatrixXf is a dynamic-size matrix of floats.
    363   *
    364   * There are also \c VectorSizeType and \c RowVectorSizeType which are self-explanatory. For example, \c Vector4cf is
    365   * a fixed-size vector of 4 complex floats.
    366   *
    367   * \sa class Matrix
    368   */
    369 
    370 #define EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, Size, SizeSuffix)   \
    371 /** \ingroup matrixtypedefs */                                    \
    372 typedef Matrix<Type, Size, Size> Matrix##SizeSuffix##TypeSuffix;  \
    373 /** \ingroup matrixtypedefs */                                    \
    374 typedef Matrix<Type, Size, 1>    Vector##SizeSuffix##TypeSuffix;  \
    375 /** \ingroup matrixtypedefs */                                    \
    376 typedef Matrix<Type, 1, Size>    RowVector##SizeSuffix##TypeSuffix;
    377 
    378 #define EIGEN_MAKE_FIXED_TYPEDEFS(Type, TypeSuffix, Size)         \
    379 /** \ingroup matrixtypedefs */                                    \
    380 typedef Matrix<Type, Size, Dynamic> Matrix##Size##X##TypeSuffix;  \
    381 /** \ingroup matrixtypedefs */                                    \
    382 typedef Matrix<Type, Dynamic, Size> Matrix##X##Size##TypeSuffix;
    383 
    384 #define EIGEN_MAKE_TYPEDEFS_ALL_SIZES(Type, TypeSuffix) \
    385 EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, 2, 2) \
    386 EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, 3, 3) \
    387 EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, 4, 4) \
    388 EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, Dynamic, X) \
    389 EIGEN_MAKE_FIXED_TYPEDEFS(Type, TypeSuffix, 2) \
    390 EIGEN_MAKE_FIXED_TYPEDEFS(Type, TypeSuffix, 3) \
    391 EIGEN_MAKE_FIXED_TYPEDEFS(Type, TypeSuffix, 4)
    392 
    393 EIGEN_MAKE_TYPEDEFS_ALL_SIZES(int,                  i)
    394 EIGEN_MAKE_TYPEDEFS_ALL_SIZES(float,                f)
    395 EIGEN_MAKE_TYPEDEFS_ALL_SIZES(double,               d)
    396 EIGEN_MAKE_TYPEDEFS_ALL_SIZES(std::complex<float>,  cf)
    397 EIGEN_MAKE_TYPEDEFS_ALL_SIZES(std::complex<double>, cd)
    398 
    399 #undef EIGEN_MAKE_TYPEDEFS_ALL_SIZES
    400 #undef EIGEN_MAKE_TYPEDEFS
    401 #undef EIGEN_MAKE_FIXED_TYPEDEFS
    402 
    403 } // end namespace Eigen
    404 
    405 #endif // EIGEN_MATRIX_H
    406