Package org.ejml.dense.row.decomposition.eig.symm

Class SymmetricQrAlgorithm_FDRM

java.lang.Object
org.ejml.dense.row.decomposition.eig.symm.SymmetricQrAlgorithm_FDRM
@Generated("org.ejml.dense.row.decomposition.eig.symm.SymmetricQrAlgorithm_DDRM")
public class SymmetricQrAlgorithm_FDRM
extends java.lang.Object

Computes the eigenvalues and eigenvectors of a symmetric tridiagonal matrix using the symmetric QR algorithm.

This implementation is based on the algorithm is sketched out in:
David S. Watkins, "Fundamentals of Matrix Computations," Second Edition. page 377-385

  • Constructor Summary

    Constructors 
    Constructor Description
    SymmetricQrAlgorithm_FDRM()
    Creates a new SymmetricQREigenvalue class that declares its own SymmetricQREigenHelper.
    SymmetricQrAlgorithm_FDRM​(SymmetricQREigenHelper_FDRM helper)  

  • Method Summary

    Modifier and Type Method Description
    float getEigenvalue​(int index)
    Returns the eigenvalue at the specified index.
    int getNumberOfEigenvalues()
    Returns the number of eigenvalues available.
    @Nullable org.ejml.data.FMatrixRMaj getQ()  
    void performStep()
    First looks for zeros and then performs the implicit single step in the QR Algorithm.
    boolean process​(int sideLength, @org.jetbrains.annotations.Nullable float[] diag, @org.jetbrains.annotations.Nullable float[] off)  
    boolean process​(int sideLength, @org.jetbrains.annotations.Nullable float[] diag, @org.jetbrains.annotations.Nullable float[] off, float[] eigenvalues)
    Computes the eigenvalue of the provided tridiagonal matrix.
    void setFastEigenvalues​(boolean fastEigenvalues)  
    void setMaxIterations​(int maxIterations)  
    void setQ​(@Nullable org.ejml.data.FMatrixRMaj q)  

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

  • Method Details

    • setMaxIterations

      public void setMaxIterations​(int maxIterations)

    • getQ

      @Nullable public @Nullable org.ejml.data.FMatrixRMaj getQ()

    • setQ

      public void setQ​(@Nullable @Nullable org.ejml.data.FMatrixRMaj q)

    • setFastEigenvalues

      public void setFastEigenvalues​(boolean fastEigenvalues)

    • getEigenvalue

      public float getEigenvalue​(int index)
      Returns the eigenvalue at the specified index.
      Parameters:
      index - Which eigenvalue.
      Returns:
      The eigenvalue.

    • getNumberOfEigenvalues

      public int getNumberOfEigenvalues()
      Returns the number of eigenvalues available.
      Returns:
      How many eigenvalues there are.

    • process

      public boolean process​(int sideLength, @Nullable @org.jetbrains.annotations.Nullable float[] diag, @Nullable @org.jetbrains.annotations.Nullable float[] off, float[] eigenvalues)
      Computes the eigenvalue of the provided tridiagonal matrix. Note that only the upper portion needs to be tridiagonal. The bottom diagonal is assumed to be the same as the top.
      Parameters:
      sideLength - Number of rows and columns in the input matrix.
      diag - Diagonal elements from tridiagonal matrix. Modified.
      off - Off diagonal elements from tridiagonal matrix. Modified.
      Returns:
      true if it succeeds and false if it fails.

    • process

      public boolean process​(int sideLength, @Nullable @org.jetbrains.annotations.Nullable float[] diag, @Nullable @org.jetbrains.annotations.Nullable float[] off)

    • performStep

      public void performStep()
      First looks for zeros and then performs the implicit single step in the QR Algorithm.