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* collection of doxygen fixes * more files with fixed doxygen comments * more doxygen fixes * more doxygen fixes * last set of doxygen comment fixes Co-authored-by: Jason Biggs <jasonb@wolfram.com>
69 lines
2.1 KiB
C++
69 lines
2.1 KiB
C++
//
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// Copyright (C) 2004-2006 Rational Discovery LLC
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//
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// @@ All Rights Reserved @@
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// This file is part of the RDKit.
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// The contents are covered by the terms of the BSD license
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// which is included in the file license.txt, found at the root
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// of the RDKit source tree.
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//
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#include <RDGeneral/export.h>
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#ifndef _RD_POWER_EIGENSOLVER_H
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#define _RD_POWER_EIGENSOLVER_H
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#include <Numerics/Vector.h>
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#include <Numerics/Matrix.h>
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#include <Numerics/SymmMatrix.h>
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namespace RDNumeric {
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namespace EigenSolvers {
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//! Compute the \c numEig largest eigenvalues and, optionally, the
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/// corresponding
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//! eigenvectors.
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/*!
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\param numEig the number of eigenvalues we are interested in
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\param mat symmetric input matrix of dimension N*N
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\param eigenValues Vector used to return the eigenvalues (size = numEig)
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\param eigenVectors Optional matrix used to return the eigenvectors (size =
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N*numEig)
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\param seed Optional values to seed the random value generator used to
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initialize the eigen vectors
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\return a boolean indicating whether or not the calculation converged.
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<b>Notes:</b>
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- The matrix, \c mat, is changed in this function
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<b>Algorithm:</b>
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We use the iterative power method, which works like this:
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\verbatim
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u = arbitrary unit vector
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tol = 0.001
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currEigVal = 0.0;
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prevEigVal = -1.0e100
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while (abs(currEigVal - prevEigVal) > tol) :
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v = Au
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prevEigVal = currEigVal
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currEigVal = v[i] // where i is the id of the largest absolute component
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u = c*v
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\endverbatim
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*/
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bool RDKIT_EIGENSOLVERS_EXPORT powerEigenSolver(
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unsigned int numEig, DoubleSymmMatrix &mat, DoubleVector &eigenValues,
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DoubleMatrix *eigenVectors = nullptr, int seed = -1);
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//! \overload
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static inline bool powerEigenSolver(unsigned int numEig, DoubleSymmMatrix &mat,
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DoubleVector &eigenValues,
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DoubleMatrix &eigenVectors, int seed = -1) {
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return powerEigenSolver(numEig, mat, eigenValues, &eigenVectors, seed);
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}
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}; // namespace EigenSolvers
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}; // namespace RDNumeric
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#endif
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