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677 lines
21 KiB
Plaintext
677 lines
21 KiB
Plaintext
namespace Eigen {
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/** \page TutorialCore Tutorial 1/3 - Core features
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\ingroup Tutorial
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<div class="eimainmenu">\ref index "Overview"
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| \b Core \b features
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| \ref TutorialGeometry "Geometry"
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| \ref TutorialAdvancedLinearAlgebra "Advanced linear algebra"
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</div>
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\b Table \b of \b contents
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- \ref TutorialCoreSimpleExampleFixedSize
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- \ref TutorialCoreSimpleExampleDynamicSize
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- \ref TutorialCoreMatrixTypes
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- \ref TutorialCoreMatrixInitialization
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- \ref TutorialCoreBasicLinearAlgebra
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- \ref TutorialCoreReductions
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- \ref TutorialCoreSubMatrix
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- \ref TutorialCoreMatrixTransformations
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- \ref TutorialCoreTriangularMatrix
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- \ref TutorialCorePerformance
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\n
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<hr>
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\section TutorialCoreSimpleExampleFixedSize Simple example with fixed-size matrices and vectors
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By fixed-size, we mean that the number of rows and columns are known at compile-time. In this case, Eigen avoids dynamic memory allocation and unroll loops. This is useful for very small sizes (typically up to 4x4).
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<table class="tutorial_code"><tr><td>
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\include Tutorial_simple_example_fixed_size.cpp
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</td>
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<td>
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output:
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\include Tutorial_simple_example_fixed_size.out
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</td></tr></table>
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<a href="#" class="top">top</a>\section TutorialCoreSimpleExampleDynamicSize Simple example with dynamic-size matrices and vectors
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Dynamic-size means that the number of rows and columns are not known at compile-time. In this case, they are stored as runtime variables and the arrays are dynamically allocated.
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<table class="tutorial_code"><tr><td>
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\include Tutorial_simple_example_dynamic_size.cpp
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</td>
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<td>
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output:
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\include Tutorial_simple_example_dynamic_size.out
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</td></tr></table>
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<a href="#" class="top">top</a>\section TutorialCoreMatrixTypes Matrix and vector types
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In Eigen, all kinds of dense matrices and vectors are represented by the template class Matrix. In most cases you can simply use one of the \ref matrixtypedefs "several convenient typedefs".
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The template class Matrix takes a number of template parameters, but for now it is enough to understand the 3 first ones (and the others can then be left unspecified):
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\code Matrix<Scalar, RowsAtCompileTime, ColsAtCompileTime> \endcode
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\li \c Scalar is the scalar type, i.e. the type of the coefficients. That is, if you want a vector of floats, choose \c float here.
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\li \c RowsAtCompileTime and \c ColsAtCompileTime are the number of rows and columns of the matrix as known at compile-time.
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For example, \c Vector3d is a typedef for \code Matrix<double, 3, 1> \endcode
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What if the matrix has dynamic-size i.e. the number of rows or cols isn't known at compile-time? Then use the special value Eigen::Dynamic. For example, \c VectorXd is a typedef for \code Matrix<double, Dynamic, 1> \endcode
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<a href="#" class="top">top</a>\section TutorialCoreMatrixInitialization Matrix and vector creation and initialization
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\subsection TutorialPredefMat PredefinedMatrix
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Eigen offers several methods to create or set matrices with coefficients equals to either a constant value, the identity matrix or even random values:
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<table class="tutorial_code">
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<tr>
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<td>Fixed-size matrix or vector</td>
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<td>Dynamic-size matrix</td>
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<td>Dynamic-size vector</td>
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</tr>
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<tr>
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<td>
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\code
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Matrix3f x;
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x = Matrix3f::Zero();
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x = Matrix3f::Ones();
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x = Matrix3f::Constant(value);
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x = Matrix3f::Identity();
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x = Matrix3f::Random();
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x.setZero();
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x.setOnes();
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x.setIdentity();
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x.setConstant(value);
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x.setRandom();
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\endcode
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</td>
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<td>
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\code
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MatrixXf x;
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x = MatrixXf::Zero(rows, cols);
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x = MatrixXf::Ones(rows, cols);
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x = MatrixXf::Constant(rows, cols, value);
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x = MatrixXf::Identity(rows, cols);
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x = MatrixXf::Random(rows, cols);
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x.setZero(rows, cols);
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x.setOnes(rows, cols);
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x.setConstant(rows, cols, value);
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x.setIdentity(rows, cols);
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x.setRandom(rows, cols);
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\endcode
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</td>
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<td>
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\code
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VectorXf x;
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x = VectorXf::Zero(size);
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x = VectorXf::Ones(size);
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x = VectorXf::Constant(size, value);
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x = VectorXf::Identity(size);
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x = VectorXf::Random(size);
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x.setZero(size);
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x.setOnes(size);
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x.setConstant(size, value);
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x.setIdentity(size);
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x.setRandom(size);
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\endcode
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</td>
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</tr>
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<tr><td colspan="3">Basis vectors \link MatrixBase::Unit [details]\endlink</td></tr>
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<tr><td>\code
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Vector3f::UnixX() // 1 0 0
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Vector3f::UnixY() // 0 1 0
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Vector3f::UnixZ() // 0 0 1
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\endcode</td><td></td><td>\code
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VectorXf::Unit(size,i)
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VectorXf::Unit(4,1) == Vector4f(0,1,0,0)
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== Vector4f::UnitY()
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\endcode
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</table>
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Here is an usage example:
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<table class="tutorial_code"><tr><td>
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\code
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cout << MatrixXf::Constant(2, 3, sqrt(2)) << endl;
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RowVector3i v;
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v.setConstant(6);
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cout << "v = " << v << endl;
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\endcode
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</td>
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<td>
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output:
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\code
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1.41 1.41 1.41
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1.41 1.41 1.41
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v = 6 6 6
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\endcode
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</td></tr></table>
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\subsection TutorialMap Map
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Any memory buffer can be mapped as an Eigen's expression:
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<table class="tutorial_code"><tr><td>
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\code
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std::vector<float> stlarray(10);
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Map<VectorXf>(&stlarray[0], stlarray.size()).setOnes();
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int data[4] = 1, 2, 3, 4;
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Matrix2i mat2x2(data);
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MatrixXi mat2x2 = Map<Matrix2i>(data);
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MatrixXi mat2x2 = Map<MatrixXi>(data,2,2);
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\endcode
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</td></tr></table>
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\subsection TutorialCommaInit CommaInitializer
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Eigen also offer a comma initializer syntax which allows you to set all the coefficients of a matrix to specific values:
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<table class="tutorial_code"><tr><td>
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\include Tutorial_commainit_01.cpp
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</td>
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<td>
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output:
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\verbinclude Tutorial_commainit_01.out
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</td></tr></table>
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Feel the above example boring ? Look at the following example where the matrix is set per block:
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<table class="tutorial_code"><tr><td>
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\include Tutorial_commainit_02.cpp
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</td>
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<td>
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output:
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\verbinclude Tutorial_commainit_02.out
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</td></tr></table>
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<span class="note">\b Side \b note: here .finished() is used to get the actual matrix object once the comma initialization
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of our temporary submatrix is done. Note that despite the appearant complexity of such an expression
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Eigen's comma initializer usually yields to very optimized code without any overhead.</span>
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<a href="#" class="top">top</a>\section TutorialCoreBasicLinearAlgebra Basic Linear Algebra
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In short all mathematically well defined operators can be used right away as in the following example:
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\code
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mat4 -= mat1*1.5 + mat2 * mat3/4;
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\endcode
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which includes two matrix scalar products ("mat1*1.5" and "mat3/4"), a matrix-matrix product ("mat2 * mat3/4"),
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a matrix addition ("+") and substraction with assignment ("-=").
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<table class="tutorial_code">
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<tr><td>
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matrix/vector product</td><td>\code
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col2 = mat1 * col1;
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row2 = row1 * mat1; row1 *= mat1;
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mat3 = mat1 * mat2; mat3 *= mat1; \endcode
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</td></tr>
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<tr><td>
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add/subtract</td><td>\code
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mat3 = mat1 + mat2; mat3 += mat1;
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mat3 = mat1 - mat2; mat3 -= mat1;\endcode
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</td></tr>
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<tr><td>
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scalar product</td><td>\code
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mat3 = mat1 * s1; mat3 = s1 * mat1; mat3 *= s1;
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mat3 = mat1 / s1; mat3 /= s1;\endcode
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</td></tr>
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<tr><td>
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\link MatrixBase::dot() dot product \endlink (inner product)</td><td>\code
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scalar = vec1.dot(vec2);\endcode
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</td></tr>
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<tr><td>
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outer product</td><td>\code
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mat = vec1 * vec2.transpose();\endcode
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</td></tr>
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<tr><td>
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\link MatrixBase::cross() cross product \endlink</td><td>\code
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#include <Eigen/Geometry>
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vec3 = vec1.cross(vec2);\endcode</td></tr>
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</table>
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In Eigen only mathematically well defined operators can be used right away,
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but don't worry, thanks to the \link Cwise .cwise() \endlink operator prefix,
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Eigen's matrices also provide a very powerful numerical container supporting
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most common coefficient wise operators:
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<table class="noborder">
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<tr><td>
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<table class="tutorial_code" style="margin-right:10pt">
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<tr><td>Coefficient wise product</td>
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<td>\code mat3 = mat1.cwise() * mat2; \endcode
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</td></tr>
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<tr><td>
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Add a scalar to all coefficients</td><td>\code
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mat3 = mat1.cwise() + scalar;
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mat3.cwise() += scalar;
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mat3.cwise() -= scalar;
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\endcode
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</td></tr>
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<tr><td>
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Coefficient wise division</td><td>\code
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mat3 = mat1.cwise() / mat2; \endcode
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</td></tr>
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<tr><td>
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Coefficient wise reciprocal</td><td>\code
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mat3 = mat1.cwise().inverse(); \endcode
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</td></tr>
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<tr><td>
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Coefficient wise comparisons \n
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(support all operators)</td><td>\code
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mat3 = mat1.cwise() < mat2;
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mat3 = mat1.cwise() <= mat2;
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mat3 = mat1.cwise() > mat2;
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etc.
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\endcode
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</td></tr></table>
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</td>
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<td><table class="tutorial_code">
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<tr><td>
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Trigo:\n sin, cos, tan</td><td>\code
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mat3 = mat1.cwise().sin();
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etc.
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\endcode
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</td></tr>
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<tr><td>
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Power:\n pow, square, cube,\n sqrt, exp, log</td><td>\code
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mat3 = mat1.cwise().square();
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mat3 = mat1.cwise().pow(5);
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mat3 = mat1.cwise().log();
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etc.
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\endcode
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</td></tr>
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<tr><td>
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min, max, absolute value</td><td>\code
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mat3 = mat1.cwise().min(mat2);
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mat3 = mat1.cwise().max(mat2);
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mat3 = mat1.cwise().abs(mat2);
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mat3 = mat1.cwise().abs2(mat2);
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\endcode</td></tr>
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</table>
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</td></tr></table>
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<span class="note">\b Side \b note: If you feel the \c .cwise() syntax is too verbose for your taste and don't bother to have non mathematical operator directly available feel free to extend MatrixBase as described \ref ExtendingMatrixBase "here".</span>
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<a href="#" class="top">top</a>\section TutorialCoreReductions Reductions
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Eigen provides several several reduction methods such as:
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\link MatrixBase::minCoeff() minCoeff() \endlink, \link MatrixBase::maxCoeff() maxCoeff() \endlink,
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\link MatrixBase::sum() sum() \endlink, \link MatrixBase::trace() trace() \endlink,
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\link MatrixBase::norm() norm() \endlink, \link MatrixBase::norm2() norm2() \endlink,
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\link MatrixBase::all() all() \endlink,and \link MatrixBase::any() any() \endlink.
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All reduction operations can be done matrix-wise,
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\link MatrixBase::colwise() column-wise \endlink or
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\link MatrixBase::rowwise() row-wise \endlink. Usage example:
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<table class="tutorial_code">
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<tr><td rowspan="3" style="border-right-style:dashed">\code
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5 3 1
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mat = 2 7 8
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9 4 6 \endcode
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</td> <td>\code mat.minCoeff(); \endcode</td><td>\code 1 \endcode</td></tr>
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<tr><td>\code mat.colwise().minCoeff(); \endcode</td><td>\code 2 3 1 \endcode</td></tr>
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<tr><td>\code mat.rowwise().minCoeff(); \endcode</td><td>\code
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1
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2
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4
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\endcode</td></tr>
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</table>
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<span class="note">\b Side \b note: The all() and any() functions are especially useful in combinaison with coeff-wise comparison operators (\ref CwiseAll "example").</span>
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<a href="#" class="top">top</a>\section TutorialCoreSubMatrix Sub matrices
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Read-write access to a \link MatrixBase::col(int) column \endlink
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or a \link MatrixBase::row(int) row \endlink of a matrix:
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\code
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mat1.row(i) = mat2.col(j);
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mat1.col(j1).swap(mat1.col(j2));
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\endcode
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Read-write access to sub-vectors:
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<table class="tutorial_code">
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<tr>
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<td>Default versions</td>
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<td>Optimized versions when the size is known at compile time</td></tr>
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<td></td>
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<tr><td>\code vec1.start(n)\endcode</td><td>\code vec1.start<n>()\endcode</td><td>the first \c n coeffs </td></tr>
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<tr><td>\code vec1.end(n)\endcode</td><td>\code vec1.end<n>()\endcode</td><td>the last \c n coeffs </td></tr>
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<tr><td>\code vec1.block(pos,n)\endcode</td><td>\code vec1.block<n>(pos)\endcode</td>
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<td>the \c size coeffs in the range [\c pos : \c pos + \c n [</td></tr>
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</table>
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Read-write access to sub-matrices:
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<table class="tutorial_code">
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<tr><td>Default versions</td>
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<td>Optimized versions when the size is known at compile time</td><td></td></tr>
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<tr>
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<td>\code mat1.block(i,j,rows,cols)\endcode
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\link MatrixBase::block(int,int,int,int) (more) \endlink</td>
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<td>\code mat1.block<rows,cols>(i,j)\endcode
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\link MatrixBase::block(int,int) (more) \endlink</td>
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<td>the \c rows x \c cols sub-matrix starting from position (\c i,\c j) </td>
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</tr>
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<tr>
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<td>\code
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mat1.corner(TopLeft,rows,cols)
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mat1.corner(TopRight,rows,cols)
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mat1.corner(BottomLeft,rows,cols)
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mat1.corner(BottomRight,rows,cols)\endcode
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\link MatrixBase::corner(CornerType,int,int) (more) \endlink</td>
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<td>\code
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mat1.corner<rows,cols>(TopLeft)
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mat1.corner<rows,cols>(TopRight)
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mat1.corner<rows,cols>(BottomLeft)
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mat1.corner<rows,cols>(BottomRight)\endcode
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\link MatrixBase::corner(CornerType) (more) \endlink</td>
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<td>the \c rows x \c cols sub-matrix \n taken in one of the four corners</td></tr>
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<tr>
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<td>\code
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vec1 = mat1.diagonal();
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mat1.diagonal() = vec1;
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\endcode
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\link MatrixBase::diagonal() (more) \endlink</td></td>
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<td></td>
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</table>
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<a href="#" class="top">top</a>\section TutorialCoreMatrixTransformations Matrix transformations
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<table class="tutorial_code">
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<tr><td>
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\link MatrixBase::transpose() transposition \endlink (read-write)</td><td>\code
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mat3 = mat1.transpose() * mat2;
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mat3.transpose() = mat1 * mat2.transpose();
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\endcode
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</td></tr>
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<tr><td>
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\link MatrixBase::adjoint() adjoint \endlink (read only)\n</td><td>\code
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mat3 = mat1.adjoint() * mat2;
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mat3 = mat1.conjugate().transpose() * mat2;
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\endcode
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</td></tr>
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<tr><td>
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\link MatrixBase::asDiagonal() make a diagonal matrix \endlink from a vector \n
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\b Note: this product is automatically optimized !</td><td>\code
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mat3 = mat1 * vec2.asDiagonal();\endcode
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</td></tr>
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<tr><td>
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\link MatrixBase::minor() minor \endlink (read-write)</td><td>\code
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mat4x4.minor(i,j) = mat3x3;
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mat3x3 = mat4x4.minor(i,j);\endcode
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</td></tr>
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</table>
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<a href="#" class="top">top</a>\section TutorialCoreTriangularMatrix Dealing with triangular matrices
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todo
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<a href="#" class="top">top</a>\section TutorialCorePerformance Notes on performances
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<table class="tutorial_code">
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<tr><td>\code
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m4 = m4 * m4;\endcode</td><td>
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auto-evaluates so no aliasing problem (performance penalty is low)</td></tr>
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<tr><td>\code
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Matrix4f other = (m4 * m4).lazy();\endcode</td><td>
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forces lazy evaluation</td></tr>
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<tr><td>\code
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m4 = m4 + m4;\endcode</td><td>
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here Eigen goes for lazy evaluation, as with most expressions</td></tr>
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<tr><td>\code
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m4 = -m4 + m4 + 5 * m4;\endcode</td><td>
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same here, Eigen chooses lazy evaluation for all that.</td></tr>
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<tr><td>\code
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m4 = m4 * (m4 + m4);\endcode</td><td>
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here Eigen chooses to first evaluate m4 + m4 into a temporary.
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indeed, here it is an optimization to cache this intermediate result.</td></tr>
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<tr><td>\code
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m3 = m3 * m4.block<3,3>(1,1);\endcode</td><td>
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here Eigen chooses \b not to evaluate block() into a temporary
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because accessing coefficients of that block expression is not more costly than accessing
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coefficients of a plain matrix.</td></tr>
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<tr><td>\code
|
|
m4 = m4 * m4.transpose();\endcode</td><td>
|
|
same here, lazy evaluation of the transpose.</td></tr>
|
|
<tr><td>\code
|
|
m4 = m4 * m4.transpose().eval();\endcode</td><td>
|
|
forces immediate evaluation of the transpose</td></tr>
|
|
</table>
|
|
|
|
*/
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/** \page TutorialGeometry Tutorial 2/3 - Geometry
|
|
\ingroup Tutorial
|
|
|
|
<div class="eimainmenu">\ref index "Overview"
|
|
| \ref TutorialCore "Core features"
|
|
| \b Geometry
|
|
| \ref TutorialAdvancedLinearAlgebra "Advanced linear algebra"
|
|
</div>
|
|
|
|
In this tutorial chapter we will shortly introduce the many possibilities offered by the \ref GeometryModule "geometry module",
|
|
namely 2D and 3D rotations and affine transformations.
|
|
|
|
\b Table \b of \b contents
|
|
- \ref TutorialGeoRotations
|
|
- \ref TutorialGeoTransformation
|
|
|
|
<a href="#" class="top">top</a>\section TutorialGeoRotations 2D and 3D Rotations
|
|
|
|
\subsection TutorialGeoRotationTypes Rotation types
|
|
|
|
|
|
<table class="tutorial_code">
|
|
<tr><td>Rotation type</td><td>Typical initialization code</td><td>Recommended usage</td></tr>
|
|
<tr><td>2D rotation from an angle</td><td>\code
|
|
Rotation2D<float> rot2(angle_in_radian);\endcode</td><td></td></tr>
|
|
<tr><td>2D rotation matrix</td><td>\code
|
|
Matrix2f rotmat2 = Rotation2Df(angle_in_radian);\endcode</td><td></td></tr>
|
|
<tr><td>3D rotation as an angle + axis</td><td>\code
|
|
AngleAxis<float> aa(angle_in_radian, Vector3f(ax,ay,az));\endcode</td><td></td></tr>
|
|
<tr><td>3D rotation as a quaternion</td><td>\code
|
|
Quaternion<float> q = AngleAxis<float>(angle_in_radian, axis);\endcode</td><td></td></tr>
|
|
<tr><td>3D rotation matrix</td><td>\code
|
|
Matrix3f rotmat3 = AngleAxis<float>(angle_in_radian, axis);\endcode</td><td></td></tr>
|
|
</table>
|
|
|
|
To transform more than a single vector the prefered representations are rotation matrices,
|
|
for other usage Rotation2D and Quaternion are the representations of choice as they are
|
|
more compact, fast and stable. AngleAxis are only useful to create other rotation objects.
|
|
|
|
\subsection TutorialGeoCommonRotationAPI Common API across rotation types
|
|
|
|
To some extent, Eigen's \ref Geometry_Module "geometry module" allows you to write
|
|
generic algorithms working on both 2D and 3D rotations of any of the five above types.
|
|
The following operation are supported:
|
|
<table class="tutorial_code">
|
|
<tr><td>Convertion from and to any types (of same space dimension)</td><td>\code
|
|
RotType2 a = RotType1();\endcode</td></tr>
|
|
<tr><td>Concatenation of two rotations</td><td>\code
|
|
rot3 = rot1 * rot2;\endcode</td></tr>
|
|
<tr><td>Apply the rotation to a vector</td><td>\code
|
|
vec2 = rot1 * vec1;\endcode</td></tr>
|
|
<tr><td>Get the inverse rotation \n (not always the most effient choice)</td><td>\code
|
|
rot2 = rot1.inverse();\endcode</td></tr>
|
|
<tr><td>Spherical interpolation \n (Rotation2D and Quaternion only)</td><td>\code
|
|
rot3 = rot1.slerp(alpha,rot2);\endcode</td></tr>
|
|
</table>
|
|
|
|
\subsection TutorialGeoEulerAngles Euler angles
|
|
<table class="tutorial_code">
|
|
<tr><td style="max-width:30em;">
|
|
Euler angles might be convenient to create rotation object.
|
|
Since there exist 24 differents convensions, they are one
|
|
the ahand pretty confusing to use. This example shows how
|
|
to create a rotation matrix according to the 2-1-2 convention.</td><td>\code
|
|
Matrix3f m;
|
|
m = AngleAxisf(angle1, Vector3f::UnitZ())
|
|
* AngleAxisf(angle2, Vector3f::UnitY())
|
|
* AngleAxisf(angle3, Vector3f::UnitZ());
|
|
\endcode</td></tr>
|
|
</table>
|
|
|
|
<a href="#" class="top">top</a>\section TutorialGeoTransformation Affine transformations
|
|
In Eigen we have chosen to not distinghish between points and vectors such that all points are
|
|
actually represented by displacement vector from the origine (pt \~ pt-0). With that in mind,
|
|
real points and vector distinguish when the rotation is applied.
|
|
<table class="tutorial_code">
|
|
<tr><td></td><td>\b 3D </td><td>\b 2D </td></tr>
|
|
<tr><td>Creation \n <span class="note">rot2D can also be an angle in radian</span></td><td>\code
|
|
Transform3f t;
|
|
t.fromPositionOrientationScale(
|
|
pos,any_3D_rotation,Vector3f(sx,sy,sz)); \endcode</td><td>\code
|
|
Transform2f t;
|
|
t.fromPositionOrientationScale(
|
|
pos,any_2D_rotation,Vector2f(sx,sy)); \endcode</td></tr>
|
|
<tr><td>Apply the transformation to a \b point </td><td>\code
|
|
Vector3f p1, p2;
|
|
p2 = t * p1;\endcode</td><td>\code
|
|
Vector2f p1, p2;
|
|
p2 = t * p1;\endcode</td></tr>
|
|
<tr><td>Apply the transformation to a \b vector </td><td>\code
|
|
Vector3f v1, v2;
|
|
v2 = t.linear() * v1;\endcode</td><td>\code
|
|
Vector2f v1, v2;
|
|
v2 = t.linear() * v1;\endcode</td></tr>
|
|
<tr><td>Concatenate two transformations</td><td>\code
|
|
t3 = t1 * t2;\endcode</td><td>\code
|
|
t3 = t1 * t2;\endcode</td></tr>
|
|
<tr><td>OpenGL compatibility</td><td>\code
|
|
glLoadMatrixf(t.data());\endcode</td><td>\code
|
|
Transform3f aux(Transform3f::Identity);
|
|
aux.linear().corner<2,2>(TopLeft) = t.linear();
|
|
aux.translation().start<2>() = t.translation();
|
|
glLoadMatrixf(aux.data());\endcode</td></tr>
|
|
<tr><td colspan="3">\b Component \b accessors</td></tr>
|
|
<tr><td>translation part</td><td>\code
|
|
t.translation() = vec3;
|
|
vec3 = t.translation();
|
|
\endcode</td><td>\code
|
|
t.translation() = vec2;
|
|
vec2 = t.translation();
|
|
\endcode</td></tr>
|
|
<tr><td>linear part</td><td>\code
|
|
t.linear() = mat3x3;
|
|
mat3x3 = t.linear();
|
|
\endcode</td><td>\code
|
|
t.linear() = mat2x2;
|
|
mat2x2 = t.linear();
|
|
\endcode</td></tr>
|
|
<tr><td colspan="3">\b Editing \b shortcuts</td></tr>
|
|
<tr><td>Applies a translation</td><td>\code
|
|
t.translate(Vector3f(tx, ty, tz));
|
|
t.pretranslate(Vector3f(tx, ty, tz));
|
|
\endcode</td><td>\code
|
|
t.translate(Vector2f(tx, ty));
|
|
t.pretranslate(Vector2f(tx, ty));
|
|
\endcode</td></tr>
|
|
<tr><td>Applies a rotation \n <span class="note">rot2D can also be an angle in radian</span></td><td>\code
|
|
t.rotate(rot3D);
|
|
t.prerotate(rot3D);
|
|
\endcode</td><td>\code
|
|
t.rotate(rot2D);
|
|
t.prerotate(rot2D);
|
|
\endcode</td></tr>
|
|
<tr><td>Applies a scaling</td><td>\code
|
|
t.scale(Vector3f(sx, sy, sz));
|
|
t.scale(Vector3f::Constant(s));
|
|
t.prescale(Vector3f(sx, sy, sz));
|
|
\endcode</td><td>\code
|
|
t.scale(Vector2f(tx, ty));
|
|
t.scale(Vector2f::Constant(s));
|
|
t.prescale(Vector2f(tx, ty));
|
|
\endcode</td></tr>
|
|
<tr><td>Applies a shear transformation \n(2D only)</td><td></td><td>\code
|
|
t.shear(sx,sy);
|
|
t.preshear(sx,sy);
|
|
\endcode</td></tr>
|
|
</table>
|
|
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
|
|
/** \page TutorialAdvancedLinearAlgebra Tutorial 3/3 - Advanced linear algebra
|
|
\ingroup Tutorial
|
|
|
|
<div class="eimainmenu">\ref index "Overview"
|
|
| \ref TutorialCore "Core features"
|
|
| \ref TutorialGeometry "Geometry"
|
|
| \b Advanced \b linear \b algebra
|
|
</div>
|
|
|
|
|
|
|
|
\b Table \b of \b contents
|
|
- \ref TutorialAdvLinearSolvers
|
|
- \ref TutorialAdvLU
|
|
- \ref TutorialAdvCholesky
|
|
- \ref TutorialAdvQR
|
|
- \ref TutorialAdvEigenProblems
|
|
|
|
\section TutorialAdvLinearSolvers Solving linear problems
|
|
todo
|
|
|
|
<a href="#" class="top">top</a>\section TutorialAdvLU LU
|
|
todo
|
|
|
|
<a href="#" class="top">top</a>\section TutorialAdvCholesky Cholesky
|
|
todo
|
|
|
|
<a href="#" class="top">top</a>\section TutorialAdvQR QR
|
|
todo
|
|
|
|
<a href="#" class="top">top</a>\section TutorialAdvEigenProblems Eigen value problems
|
|
todo
|
|
|
|
*/
|
|
|
|
}
|