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Document Tridiagonalization class, remove unused types.

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This commit is contained in:
Jitse Niesen
2010-05-01 17:52:16 +01:00
parent d9c1224133
commit afed0ef90d
7 changed files with 263 additions and 44 deletions
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11
doc/snippets/Tridiagonalization_Tridiagonalization_MatrixType.cpp Normal file
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MatrixXd X = MatrixXd::Random(5,5);
MatrixXd A = X + X.transpose();
cout << "Here is a random symmetric 5x5 matrix:" << endl << A << endl << endl;
Tridiagonalization<MatrixXd> triOfA(A);
cout << "The orthogonal matrix Q is:" << endl << triOfA.matrixQ() << endl;
cout << "The tridiagonal matrix T is:" << endl << triOfA.matrixT() << endl << endl;
MatrixXd Q = triOfA.matrixQ();
MatrixXd T = triOfA.matrixT();
cout << "Q * T * Q^T = " << endl << Q * T * Q.transpose() << endl;

9
doc/snippets/Tridiagonalization_compute.cpp Normal file
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Tridiagonalization<MatrixXf> tri;
MatrixXf X = MatrixXf::Random(4,4);
MatrixXf A = X + X.transpose();
tri.compute(A);
cout << "The matrix T in the tridiagonal decomposition of A is: " << endl;
cout << tri.matrixT() << endl;
tri.compute(2*A); // re-use tri to compute eigenvalues of 2A
cout << "The matrix T in the tridiagonal decomposition of 2A is: " << endl;
cout << tri.matrixT() << endl;

10
doc/snippets/Tridiagonalization_decomposeInPlace.cpp Normal file
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MatrixXd X = MatrixXd::Random(5,5);
MatrixXd A = X + X.transpose();
cout << "Here is a random symmetric 5x5 matrix:" << endl << A << endl << endl;
VectorXd diag(5);
VectorXd subdiag(4);
Tridiagonalization<MatrixXd>::decomposeInPlace(A, diag, subdiag);
cout << "The orthogonal matrix Q is:" << endl << A << endl;
cout << "The diagonal of the tridiagonal matrix T is:" << endl << diag << endl;
cout << "The subdiagonal of the tridiagonal matrix T is:" << endl << subdiag << endl;

13
doc/snippets/Tridiagonalization_diagonal.cpp Normal file
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MatrixXcd X = MatrixXcd::Random(4,4);
MatrixXcd A = X + X.adjoint();
cout << "Here is a random self-adjoint 4x4 matrix:" << endl << A << endl << endl;
Tridiagonalization<MatrixXcd> triOfA(A);
MatrixXcd T = triOfA.matrixT();
cout << "The tridiagonal matrix T is:" << endl << triOfA.matrixT() << endl << endl;
cout << "We can also extract the diagonals of T directly ..." << endl;
VectorXd diag = triOfA.diagonal();
cout << "The diagonal is:" << endl << diag << endl;
VectorXd subdiag = triOfA.subDiagonal();
cout << "The subdiagonal is:" << endl << subdiag << endl;

6
doc/snippets/Tridiagonalization_householderCoefficients.cpp Normal file
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Matrix4d X = Matrix4d::Random(4,4);
Matrix4d A = X + X.transpose();
cout << "Here is a random symmetric 4x4 matrix:" << endl << A << endl;
Tridiagonalization<Matrix4d> triOfA(A);
Vector3d hc = triOfA.householderCoefficients();
cout << "The vector of Householder coefficients is:" << endl << hc << endl;

8
doc/snippets/Tridiagonalization_packedMatrix.cpp Normal file
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Matrix4d X = Matrix4d::Random(4,4);
Matrix4d A = X + X.transpose();
cout << "Here is a random symmetric 4x4 matrix:" << endl << A << endl;
Tridiagonalization<Matrix4d> triOfA(A);
Matrix4d pm = triOfA.packedMatrix();
cout << "The packed matrix M is:" << endl << pm << endl;
cout << "The diagonal and subdiagonal corresponds to the matrix T, which is:"
<< endl << triOfA.matrixT() << endl;