C++矩阵处理工具Eigen类浅析

参考

http://eigen.tuxfamily.org/dox/classEigen_1_1Matrix.html

1.Matrix 矩阵

矩阵类多用于单列vector和单行的vector，多用于密集型矩阵或者vectors容器。Vector是只有一列的矩阵，row-vector是只有一行的矩阵。可以定义为固定大小或者动态大小。

template<typename _Scalar, int _Rows, int _Cols, int _Options, int _MaxRows, int _MaxCols>

class Eigen::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:（类型，行、列）

Template Parameters

_Scalar@anchor	matrix_tparam_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

2.定义类型

Typedefs
typedef Matrix< std::complex < double >, 2, 2 >	Matrix2cd
typedef Matrix< std::complex < float >, 2, 2 >	Matrix2cf
typedef Matrix< double, 2, 2 >	Matrix2d
typedef Matrix< float, 2, 2 >	Matrix2f
typedef Matrix< int, 2, 2 >	Matrix2i
typedef Matrix< std::complex < double >, 2, Dynamic >	Matrix2Xcd
typedef Matrix< std::complex < float >, 2, Dynamic >	Matrix2Xcf
typedef Matrix< double, 2, Dynamic >	Matrix2Xd
typedef Matrix< float, 2, Dynamic >	Matrix2Xf
typedef Matrix< int, 2, Dynamic >	Matrix2Xi
typedef Matrix< std::complex < double >, 3, 3 >	Matrix3cd
typedef Matrix< std::complex < float >, 3, 3 >	Matrix3cf
typedef Matrix< double, 3, 3 >	Matrix3d
typedef Matrix< float, 3, 3 >	Matrix3f
typedef Matrix< int, 3, 3 >	Matrix3i
typedef Matrix< std::complex < double >, 3, Dynamic >	Matrix3Xcd
typedef Matrix< std::complex < float >, 3, Dynamic >	Matrix3Xcf
typedef Matrix< double, 3, Dynamic >	Matrix3Xd
typedef Matrix< float, 3, Dynamic >	Matrix3Xf
typedef Matrix< int, 3, Dynamic >	Matrix3Xi
typedef Matrix< std::complex < double >, 4, 4 >	Matrix4cd
typedef Matrix< std::complex < float >, 4, 4 >	Matrix4cf
typedef Matrix< double, 4, 4 >	Matrix4d
typedef Matrix< float, 4, 4 >	Matrix4f
typedef Matrix< int, 4, 4 >	Matrix4i
typedef Matrix< std::complex < double >, 4, Dynamic >	Matrix4Xcd
typedef Matrix< std::complex < float >, 4, Dynamic >	Matrix4Xcf
typedef Matrix< double, 4, Dynamic >	Matrix4Xd
typedef Matrix< float, 4, Dynamic >	Matrix4Xf
typedef Matrix< int, 4, Dynamic >	Matrix4Xi
typedef Matrix< std::complex < double >, Dynamic, 2 >	MatrixX2cd
typedef Matrix< std::complex < float >, Dynamic, 2 >	MatrixX2cf
typedef Matrix< double, Dynamic, 2 >	MatrixX2d
typedef Matrix< float, Dynamic, 2 >	MatrixX2f
typedef Matrix< int, Dynamic, 2 >	MatrixX2i
typedef Matrix< std::complex < double >, Dynamic, 3 >	MatrixX3cd
typedef Matrix< std::complex < float >, Dynamic, 3 >	MatrixX3cf
typedef Matrix< double, Dynamic, 3 >	MatrixX3d
typedef Matrix< float, Dynamic, 3 >	MatrixX3f
typedef Matrix< int, Dynamic, 3 >	MatrixX3i
typedef Matrix< std::complex < double >, Dynamic, 4 >	MatrixX4cd
typedef Matrix< std::complex < float >, Dynamic, 4 >	MatrixX4cf
typedef Matrix< double, Dynamic, 4 >	MatrixX4d
typedef Matrix< float, Dynamic, 4 >	MatrixX4f
typedef Matrix< int, Dynamic, 4 >	MatrixX4i
typedef Matrix< std::complex < double >, Dynamic, Dynamic >	MatrixXcd
typedef Matrix< std::complex < float >, Dynamic, Dynamic >	MatrixXcf
typedef Matrix< double, Dynamic, Dynamic >	MatrixXd
typedef Matrix< float, Dynamic, Dynamic >	MatrixXf
typedef Matrix< int, Dynamic, Dynamic >	MatrixXi
typedef Matrix< std::complex < double >, 1, 2 >	RowVector2cd
typedef Matrix< std::complex < float >, 1, 2 >	RowVector2cf
typedef Matrix< double, 1, 2 >	RowVector2d
typedef Matrix< float, 1, 2 >	RowVector2f
typedef Matrix< int, 1, 2 >	RowVector2i
typedef Matrix< std::complex < double >, 1, 3 >	RowVector3cd
typedef Matrix< std::complex < float >, 1, 3 >	RowVector3cf
typedef Matrix< double, 1, 3 >	RowVector3d
typedef Matrix< float, 1, 3 >	RowVector3f
typedef Matrix< int, 1, 3 >	RowVector3i
typedef Matrix< std::complex < double >, 1, 4 >	RowVector4cd
typedef Matrix< std::complex < float >, 1, 4 >	RowVector4cf
typedef Matrix< double, 1, 4 >	RowVector4d
typedef Matrix< float, 1, 4 >	RowVector4f
typedef Matrix< int, 1, 4 >	RowVector4i
typedef Matrix< std::complex < double >, 1, Dynamic >	RowVectorXcd
typedef Matrix< std::complex < float >, 1, Dynamic >	RowVectorXcf
typedef Matrix< double, 1, Dynamic >	RowVectorXd
typedef Matrix< float, 1, Dynamic >	RowVectorXf
typedef Matrix< int, 1, Dynamic >	RowVectorXi
typedef Matrix< std::complex < double >, 2, 1 >	Vector2cd
typedef Matrix< std::complex < float >, 2, 1 >	Vector2cf
typedef Matrix< double, 2, 1 >	Vector2d
typedef Matrix< float, 2, 1 >	Vector2f
typedef Matrix< int, 2, 1 >	Vector2i
typedef Matrix< std::complex < double >, 3, 1 >	Vector3cd
typedef Matrix< std::complex < float >, 3, 1 >	Vector3cf
typedef Matrix< double, 3, 1 >	Vector3d
typedef Matrix< float, 3, 1 >	Vector3f
typedef Matrix< int, 3, 1 >	Vector3i
typedef Matrix< std::complex < double >, 4, 1 >	Vector4cd
typedef Matrix< std::complex < float >, 4, 1 >	Vector4cf
typedef Matrix< double, 4, 1 >	Vector4d
typedef Matrix< float, 4, 1 >	Vector4f
typedef Matrix< int, 4, 1 >	Vector4i
typedef Matrix< std::complex < double >, Dynamic, 1 >	VectorXcd
typedef Matrix< std::complex < float >, Dynamic, 1 >	VectorXcf
typedef Matrix< double, Dynamic, 1 >	VectorXd
typedef Matrix< float, Dynamic, 1 >	VectorXf
typedef Matrix< int, Dynamic, 1 >	VectorXi