RDKit: PowerEigenSolver.h Source File

| RDKit Open-source cheminformatics and machine learning.

Loading...
Searching...
No Matches
PowerEigenSolver.h
Go to the documentation of this file.
1//
2// Copyright (C) 2004-2006 Rational Discovery LLC
3//
4// @@ All Rights Reserved @@
5// This file is part of the RDKit.
6// The contents are covered by the terms of the BSD license
7// which is included in the file license.txt, found at the root
8// of the RDKit source tree.
9//
10
11#include <RDGeneral/export.h>
12#ifndef _RD_POWER_EIGENSOLVER_H
13#define _RD_POWER_EIGENSOLVER_H
14
15#include <Numerics/Vector.h>
16#include <Numerics/Matrix.h>
17#include <Numerics/SymmMatrix.h>
18
19namespace RDNumeric {
20 namespace EigenSolvers {
21//! Compute the \c numEig largest eigenvalues and, optionally, the
22/// corresponding
23//! eigenvectors.
24/*!
25
26\param numEig the number of eigenvalues we are interested in
27\param mat symmetric input matrix of dimension N*N
28\param eigenValues Vector used to return the eigenvalues (size = numEig)
29\param eigenVectors Optional matrix used to return the eigenvectors (size =
30N*numEig)
31\param seed Optional values to seed the random value generator used to
32 initialize the eigen vectors
33\return a boolean indicating whether or not the calculation converged.
34
35<b>Notes:</b>
36- The matrix, \c mat, is changed in this function
37
38<b>Algorithm:</b>
39
40We use the iterative power method, which works like this:
41
42\verbatim
43 u = arbitrary unit vector
44 tol = 0.001
45 currEigVal = 0.0;
46 prevEigVal = -1.0e100
47 while (abs(currEigVal - prevEigVal) > tol) :
48 v = Au
49 prevEigVal = currEigVal
50 currEigVal = v[i] // where i is the id of the largest absolute component
51 u = c*v
52\endverbatim
53
54
55*/
56 bool RDKIT_EIGENSOLVERS_EXPORT powerEigenSolver(
57 unsigned int numEig, DoubleSymmMatrix &mat, DoubleVector &eigenValues,
58 DoubleMatrix *eigenVectors = nullptr, int seed = -1);
59//! \overload
60 static inline bool powerEigenSolver(unsigned int numEig, DoubleSymmMatrix &mat,
61 DoubleVector &eigenValues,
62 DoubleMatrix &eigenVectors, int seed = -1) {
63 return powerEigenSolver(numEig, mat, eigenValues, &eigenVectors, seed);
64}
65}; // namespace EigenSolvers
66}; // namespace RDNumeric
67
68#endif
Matrix.h
SymmMatrix.h
Vector.h
export.h
RDKIT_EIGENSOLVERS_EXPORT
#define RDKIT_EIGENSOLVERS_EXPORT
Definition export.h:153
RDNumeric::EigenSolvers
Definition PowerEigenSolver.h:20
RDNumeric::EigenSolvers::powerEigenSolver
bool RDKIT_EIGENSOLVERS_EXPORT powerEigenSolver(unsigned int numEig, DoubleSymmMatrix &mat, DoubleVector &eigenValues, DoubleMatrix *eigenVectors=nullptr, int seed=-1)
RDNumeric
Definition AlignPoints.h:18
RDNumeric::DoubleSymmMatrix
SymmMatrix< double > DoubleSymmMatrix
Definition SymmMatrix.h:339
RDNumeric::DoubleVector
Vector< double > DoubleVector
Definition Vector.h:296
RDNumeric::DoubleMatrix
Matrix< double > DoubleMatrix
Definition Matrix.h:338