RWEigDecomp< TypeT > Class Template Reference
[Nonsymmetric Eigenvalue Decomposition]

Encapsulates the eigenvalues and eigenvectors of a nonsymmetric matrix. More...

#include <rw/lapack/eig.h>

List of all members.

Public Member Functions
	RWEigDecomp ()
	RWEigDecomp (const RWEigDecomp< double > &A)
	RWEigDecomp (const RWGenMat< TypeT > &A, bool computeVecs=true)
void	factor (const RWGenMat< TypeT > &A, bool computeVecs=true)
void	operator= (const RWEigDecomp< TypeT > &)
unsigned	cols () const
DComplex	eigenValue (int i) const
const RWMathVec< DComplex >	eigenValues () const
const RWMathVec< DComplex >	leftEigenVector (int i) const
const RWGenMat< DComplex >	leftEigenVectors () const
const RWMathVec< DComplex >	rightEigenVector (int i) const
const RWGenMat< DComplex >	rightEigenVectors () const
bool	good () const
bool	inaccurate () const
bool	fail () const
unsigned	numEigenValues () const
unsigned	numLeftEigenVectors () const
unsigned	numRightEigenVectors () const
unsigned	rows () const

---

Detailed Description

template<class TypeT>
class RWEigDecomp< TypeT >

The class RWEigDecomp<T> encapsulates the eigenvalues and eigenvectors of a nonsymmetric matrix. You can construct an eigenvalue decomposition object in two ways:

• Use the decomposition class constructor. This has the advantage of simplicity, but allows only limited control over the computation. Your only choice is whether or not to compute eigenvectors.
• Use an eigenvalue server object. This gives you more precise control over the computation. See RWEigServer<T> in this manual for details.

Synopsis

 #include <rw/lapack/eig.h>
 
 RWEigDecomp<double> eig(A);      // A is an
                                   // RWGenMat<double>

Examples

 #include <iostream>
 #include <rw/lapack/eig.h>
 
 int main()
 {
    RWGenMat<double> A;
    std::cin >> A;
    RWEigDecomp<double> eig(A);
    std::cout << "eigenvalues: " << eig.eigenValues() <<
                 std::endl;
    std::cout << "left eigenvectors: " << eig.leftEigenVectors() 
               << std::endl;
    std::cout << "right vectors: " << eig.rightEigenVectors() << endl;
    return 0;
 }

---

Constructor & Destructor Documentation

template<class TypeT>

RWEigDecomp< TypeT >::RWEigDecomp

(

)

Default constructor. Builds a decomposition of a 0 x 0 matrix.

template<class TypeT>

RWEigDecomp< TypeT >::RWEigDecomp

(

const RWEigDecomp< double > &

A

)

Copy and precision conversion constructors. Where possible, data is referenced for efficiency.

template<class TypeT>

RWEigDecomp< TypeT >::RWEigDecomp	(	const RWGenMat< TypeT > &	A,
		bool	computeVecs = true
	)

Constructs a representation of the eigenvalues and eigenvectors of the matrix A. The boolean parameter computeVecs controls whether eigenvectors are computed.

---

Member Function Documentation

template<class TypeT>

unsigned RWEigDecomp< TypeT >::cols

(

)

const [inline]

Returns the number of columns in the decomposed matrix.

template<class TypeT>

DComplex RWEigDecomp< TypeT >::eigenValue

(

int

i

)

const

Returns the i^th eigenvalue.

template<class TypeT>

const RWMathVec<DComplex> RWEigDecomp< TypeT >::eigenValues

(

)

const [inline]

Returns a vector of all computed eigenvalues.

template<class TypeT>

void RWEigDecomp< TypeT >::factor	(	const RWGenMat< TypeT > &	A,
		bool	computeVecs = true
	)

Constructs a representation of the eigenvalues and eigenvectors of the matrix A. The boolean parameter computeVecs controls whether eigenvectors are computed. The current contents of the decomposition are lost.

template<class TypeT>

bool RWEigDecomp< TypeT >::fail

(

)

const

Returns true if an eigenvalue or eigenvector that is supposed to be computed fails to be computed.

template<class TypeT>

bool RWEigDecomp< TypeT >::good

(

)

const

Returns true if all desired eigenvalues and eigenvectors are successfully computed to full desired accuracy.

template<class TypeT>

bool RWEigDecomp< TypeT >::inaccurate

(

)

const

Returns true if either an eigenvalue or eigenvector that is supposed to be computed fails to be computed, or some of the computed quantities are not computed to full desired accuracy.

template<class TypeT>

const RWMathVec<DComplex> RWEigDecomp< TypeT >::leftEigenVector

(

int

i

)

const

Returns the i^th left eigenvector.

template<class TypeT>

const RWGenMat<DComplex> RWEigDecomp< TypeT >::leftEigenVectors

(

)

const

Returns a vector of all computed left eigenvectors.

template<class TypeT>

unsigned RWEigDecomp< TypeT >::numEigenValues

(

)

const [inline]

Returns the number of eigenvalues or eigenvectors represented in this object.

template<class TypeT>

unsigned RWEigDecomp< TypeT >::numLeftEigenVectors

(

)

const [inline]

Returns the number of eigenvalues or eigenvectors represented in this object.

template<class TypeT>

unsigned RWEigDecomp< TypeT >::numRightEigenVectors

(

)

const [inline]

Returns the number of eigenvalues or eigenvectors represented in this object.

template<class TypeT>

void RWEigDecomp< TypeT >::operator=

(

const RWEigDecomp< TypeT > &

)

Assigns the passed value to this decomposition. The current contents of the decomposition are lost.

template<class TypeT>

const RWMathVec<DComplex> RWEigDecomp< TypeT >::rightEigenVector

(

int

i

)

const

Returns the i^th right eigenvector.

template<class TypeT>

const RWGenMat<DComplex> RWEigDecomp< TypeT >::rightEigenVectors

(

)

const

Returns a matrix of all computed right eigenvectors.

template<class TypeT>

unsigned RWEigDecomp< TypeT >::rows

(

)

const [inline]

Returns the number of rows in the decomposed matrix.