The matrix class, also used for vectors and row-vectors. More...
#include <Matrix.h>
Public Types | |
| enum | { Options = _Options } |
| enum | { NeedsToAlign } |
| typedef PlainObjectBase< Matrix > | Base |
| Base class typedef. | |
| typedef Base::PlainObject | PlainObject |
Public Member Functions | |
| Index | innerStride () const |
| EIGEN_STRONG_INLINE | Matrix () |
| Default constructor. | |
| Matrix (internal::constructor_without_unaligned_array_assert) | |
| EIGEN_STRONG_INLINE | Matrix (Index dim) |
| Constructs a vector or row-vector with given dimension. . | |
| template<typename T0 , typename T1 > | |
| EIGEN_STRONG_INLINE | Matrix (const T0 &x, const T1 &y) |
| EIGEN_STRONG_INLINE | Matrix (const Scalar &x, const Scalar &y, const Scalar &z) |
| Constructs an initialized 3D vector with given coefficients. | |
| EIGEN_STRONG_INLINE | Matrix (const Scalar &x, const Scalar &y, const Scalar &z, const Scalar &w) |
| Constructs an initialized 4D vector with given coefficients. | |
| Matrix (const Scalar *data) | |
| template<typename OtherDerived > | |
| EIGEN_STRONG_INLINE | Matrix (const MatrixBase< OtherDerived > &other) |
| Constructor copying the value of the expression other. | |
| EIGEN_STRONG_INLINE | Matrix (const Matrix &other) |
| Copy constructor. | |
| template<typename OtherDerived > | |
| EIGEN_STRONG_INLINE | Matrix (const ReturnByValue< OtherDerived > &other) |
| Copy constructor with in-place evaluation. | |
| template<typename OtherDerived > | |
| EIGEN_STRONG_INLINE | Matrix (const EigenBase< OtherDerived > &other) |
| Copy constructor for generic expressions. | |
| template<typename OtherDerived > | |
| Matrix (const RotationBase< OtherDerived, ColsAtCompileTime > &r) | |
| Constructs a Dim x Dim rotation matrix from the rotation r. | |
| EIGEN_STRONG_INLINE Matrix & | operator= (const Matrix &other) |
| Assigns matrices to each other. | |
| template<typename OtherDerived > | |
| EIGEN_STRONG_INLINE Matrix & | operator= (const MatrixBase< OtherDerived > &other) |
| template<typename OtherDerived > | |
| EIGEN_STRONG_INLINE Matrix & | operator= (const EigenBase< OtherDerived > &other) |
| Copies the generic expression other into *this. | |
| template<typename OtherDerived > | |
| EIGEN_STRONG_INLINE Matrix & | operator= (const ReturnByValue< OtherDerived > &func) |
| template<typename OtherDerived > | |
| Matrix & | operator= (const RotationBase< OtherDerived, ColsAtCompileTime > &r) |
| Set a Dim x Dim rotation matrix from the rotation r. | |
| Index | outerStride () const |
| template<typename OtherDerived > | |
| void | swap (MatrixBase< OtherDerived > const &other) |
Friends | |
| struct | internal::conservative_resize_like_impl |
Detailed Description
template<typename _Scalar, int _Rows, int _Cols, int _Options, int _MaxRows, int _MaxCols>
class Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >
The matrix class, also used for vectors and row-vectors.
The Matrix class is the work-horse for all dense (note) matrices and vectors within Eigen. Vectors are matrices with one column, and row-vectors are matrices with one row.
The Matrix class encompasses both fixed-size and dynamic-size objects (note).
The first three template parameters are required:
- Template Parameters:
-
_Scalar Numeric type, e.g. float, double, int or std::complex<float>. User defined sclar types are supported as well (see here). _Rows Number of rows, or Dynamic _Cols Number of columns, or Dynamic
The remaining template parameters are optional -- in most cases you don't have to worry about them.
- Template Parameters:
-
_Options A combination of either RowMajor or ColMajor, and of either AutoAlign or DontAlign. The former controls storage order, and defaults to column-major. The latter controls alignment, which is required for vectorization. It defaults to aligning matrices except for fixed sizes that aren't a multiple of the packet size. _MaxRows Maximum number of rows. Defaults to _Rows (note). _MaxCols Maximum number of columns. Defaults to _Cols (note).
Eigen provides a number of typedefs covering the usual cases. Here are some examples:
Matrix2dis a 2x2 square matrix of doubles (Matrix<double, 2, 2>)Vector4fis a vector of 4 floats (Matrix<float, 4, 1>)RowVector3iis a row-vector of 3 ints (Matrix<int, 1, 3>)
MatrixXfis a dynamic-size matrix of floats (Matrix<float, Dynamic, Dynamic>)VectorXfis a dynamic-size vector of floats (Matrix<float, Dynamic, 1>)
Matrix2Xfis a partially fixed-size (dynamic-size) matrix of floats (Matrix<float, 2, Dynamic>)MatrixX3dis a partially dynamic-size (fixed-size) matrix of double (Matrix<double, Dynamic, 3>)
See this page for a complete list of predefined Matrix and Vector typedefs.
You can access elements of vectors and matrices using normal subscripting:
Eigen::VectorXd v(10); v[0] = 0.1; v[1] = 0.2; v(0) = 0.3; v(1) = 0.4; Eigen::MatrixXi m(10, 10); m(0, 1) = 1; m(0, 2) = 2; m(0, 3) = 3;
This class can be extended with the help of the plugin mechanism described on the page Customizing/Extending Eigen by defining the preprocessor symbol EIGEN_MATRIX_PLUGIN.
Some notes:
- Dense versus sparse:
This Matrix class handles dense, not sparse matrices and vectors. For sparse matrices and vectors, see the Sparse module.
Dense matrices and vectors are plain usual arrays of coefficients. All the coefficients are stored, in an ordinary contiguous array. This is unlike Sparse matrices and vectors where the coefficients are stored as a list of nonzero coefficients.
- Fixed-size versus dynamic-size:
Fixed-size means that the numbers of rows and columns are known are compile-time. In this case, Eigen allocates the array of coefficients as a fixed-size array, as a class member. This makes sense for very small matrices, typically up to 4x4, sometimes up to 16x16. Larger matrices should be declared as dynamic-size even if one happens to know their size at compile-time.
Dynamic-size means that the numbers of rows or columns are not necessarily known at compile-time. In this case they are runtime variables, and the array of coefficients is allocated dynamically on the heap.
Note that dense matrices, be they Fixed-size or Dynamic-size, do not expand dynamically in the sense of a std::map. If you want this behavior, see the Sparse module.
- _MaxRows and _MaxCols:
- In most cases, one just leaves these parameters to the default values. These parameters mean the maximum size of rows and columns that the matrix may have. They are useful in cases when the exact numbers of rows and columns are not known are compile-time, but it is known at compile-time that they cannot exceed a certain value. This happens when taking dynamic-size blocks inside fixed-size matrices: in this case _MaxRows and _MaxCols are the dimensions of the original matrix, while _Rows and _Cols are Dynamic.
- See also:
- MatrixBase for the majority of the API methods for matrices, The class hierarchy, Storage orders
Member Typedef Documentation
| typedef PlainObjectBase<Matrix> Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::Base |
Base class typedef.
- See also:
- PlainObjectBase
Reimplemented from PlainObjectBase< Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols > >.
Reimplemented in GeneralProduct< Lhs, Rhs, InnerProduct >.
| typedef Base::PlainObject Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::PlainObject |
Member Enumeration Documentation
| anonymous enum |
| anonymous enum |
Constructor & Destructor Documentation
| EIGEN_STRONG_INLINE Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::Matrix | ( | ) | [inline, explicit] |
Default constructor.
For fixed-size matrices, does nothing.
For dynamic-size matrices, creates an empty matrix of size 0. Does not allocate any array. Such a matrix is called a null matrix. This constructor is the unique way to create null matrices: resizing a matrix to 0 is not supported.
- See also:
- resize(Index,Index)
| Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::Matrix | ( | internal::constructor_without_unaligned_array_assert | ) | [inline] |
| EIGEN_STRONG_INLINE Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::Matrix | ( | Index | dim | ) | [inline, explicit] |
| EIGEN_STRONG_INLINE Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::Matrix | ( | const T0 & | x, |
| const T1 & | y | ||
| ) | [inline] |
| EIGEN_STRONG_INLINE Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::Matrix | ( | const MatrixBase< OtherDerived > & | other | ) | [inline] |
| EIGEN_STRONG_INLINE Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::Matrix | ( | const Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols > & | other | ) | [inline] |
| EIGEN_STRONG_INLINE Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::Matrix | ( | const ReturnByValue< OtherDerived > & | other | ) | [inline] |
| EIGEN_STRONG_INLINE Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::Matrix | ( | const EigenBase< OtherDerived > & | other | ) | [inline] |
Copy constructor for generic expressions.
| Matrix< _Scalar, _Rows, _Cols, _Storage, _MaxRows, _MaxCols >::Matrix | ( | const RotationBase< OtherDerived, ColsAtCompileTime > & | r | ) | [explicit] |
Constructs a Dim x Dim rotation matrix from the rotation r.
Constructs a Dim x Dim rotation matrix from the rotation r
Definition at line 77 of file Eigen2Support/Geometry/RotationBase.h.
Member Function Documentation
| Index Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::innerStride | ( | ) | const [inline] |
| EIGEN_STRONG_INLINE Matrix& Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::operator= | ( | const Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols > & | other | ) | [inline] |
| EIGEN_STRONG_INLINE Matrix& Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::operator= | ( | const MatrixBase< OtherDerived > & | other | ) | [inline] |
| EIGEN_STRONG_INLINE Matrix& Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::operator= | ( | const EigenBase< OtherDerived > & | other | ) | [inline] |
Copies the generic expression other into *this.
The expression must provide a (templated) evalTo(Derived& dst) const function which does the actual job. In practice, this allows any user to write its own special matrix without having to modify MatrixBase
- Returns:
- a reference to *this.
Reimplemented from PlainObjectBase< Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols > >.
| EIGEN_STRONG_INLINE Matrix& Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::operator= | ( | const ReturnByValue< OtherDerived > & | func | ) | [inline] |
Reimplemented from PlainObjectBase< Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols > >.
| Matrix< _Scalar, _Rows, _Cols, _Storage, _MaxRows, _MaxCols > & Matrix< _Scalar, _Rows, _Cols, _Storage, _MaxRows, _MaxCols >::operator= | ( | const RotationBase< OtherDerived, ColsAtCompileTime > & | r | ) |
Set a Dim x Dim rotation matrix from the rotation r.
Set a Dim x Dim rotation matrix from the rotation r
Definition at line 91 of file Eigen2Support/Geometry/RotationBase.h.
| Index Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::outerStride | ( | ) | const [inline] |
| void Matrix< _Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols >::swap | ( | MatrixBase< OtherDerived > const & | other | ) | [inline] |
Friends And Related Function Documentation
friend struct internal::conservative_resize_like_impl [friend] |
The documentation for this class was generated from the following files: