gov.sandia.cognition.math.matrix.decomposition
Interface EigenDecomposition

All Known Implementing Classes:
AbstractEigenDecomposition, EigenDecompositionRightMTJ

@CodeReview(reviewer="Jonathan McClain",
            date="2006-05-16",
            changesNeeded=false,
            comments="Interface looks fine.")
@PublicationReference(author="Wikipedia",
                      title="Eigendecomposition of a matrix",
                      type=WebPage,
                      year=2010,
                      url="http://en.wikipedia.org/wiki/Eigendecomposition_of_a_matrix")
public interface EigenDecomposition

Performs a right eigendecomposition for symmetric or asymmetric matrices

Since:
1.0
Author:
Kevin R. Dixon

Method Summary
 ComplexNumber getEigenValue(int index)
          Gets the complex-valued (potentially real and/or imaginary) eigenvalue specified by the index "index"
 ComplexNumber[] getEigenValues()
          Returns the array of complex-valued eigenvalues, the eigenvalues may be sorted in descending order of the magnitude of the eigenvalue, or they may be unsorted, depending on the specific implementation used
 Matrix getEigenVectorsImaginaryPart()
          Returns a matrix with the imaginary parts of the right eigenvalues of the underlying matrix
 Matrix getEigenVectorsRealPart()
          Returns a matrix with the real parts of the right eigenvalues of the underlying matrix
 ComplexNumber getLogDeterminant()
          Computes the natural logarithm determinant from the collection of eigenvalues
 

Method Detail

getEigenValue

ComplexNumber getEigenValue(int index)
Gets the complex-valued (potentially real and/or imaginary) eigenvalue specified by the index "index"

Parameters:
index - zero-based eigenvalue index to return
Returns:
ComplexNumber that specifies the eigenvalue

getEigenValues

ComplexNumber[] getEigenValues()
Returns the array of complex-valued eigenvalues, the eigenvalues may be sorted in descending order of the magnitude of the eigenvalue, or they may be unsorted, depending on the specific implementation used

Returns:
array of complex-valued eigenvalues

getEigenVectorsRealPart

Matrix getEigenVectorsRealPart()
Returns a matrix with the real parts of the right eigenvalues of the underlying matrix

Returns:
matrix containing the real parts of the right eivenvalues

getEigenVectorsImaginaryPart

Matrix getEigenVectorsImaginaryPart()
Returns a matrix with the imaginary parts of the right eigenvalues of the underlying matrix

Returns:
matrix containing the imaginary parts of the right eivenvalues

getLogDeterminant

ComplexNumber getLogDeterminant()
Computes the natural logarithm determinant from the collection of eigenvalues

Returns:
natural logarithm of the determinant