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eigsort

Version:
    Last Modified: March 15, 2017

    Computes eigenvalues and eigenvectors for real or complex square matrices. eigsort(a) solves the standard problem a x = lambda*x. eigsort(a,b) solves the general problem a x = lambda*b x. Out of all possible eigenvalues and eigenvectors, MathScript returns only six according to the order you specify.

    Syntax

    ev = eigsort(a)
    ev = eigsort(a, k)
    ev = eigsort(a, k, order)
    ev = eigsort(a, b)
    ev = eigsort(a, b, k)
    ev = eigsort(a, b, k, order)
    [evec, evdiag] = eigsort(a)
    [evec, evdiag] = eigsort(a, k)
    [evec, evdiag] = eigsort(a, k, order)
    [evec, evdiag] = eigsort(a, b)
    [evec, evdiag] = eigsort(a, b, k)
    [evec, evdiag] = eigsort(a, b, k, order)
    Legacy name: eigs

    Inputs

    a

    Square matrix whose dependent matrices are also square.

    k

    Number of eigenvalues to be calculated.

    Default: 6

    b

    Matrix of the same size as a.

    order

    Determines, which eigenvalues and eigenvectors to compute. order is a string that accepts the following values.

    Name Description
    'LM' (default)

    Sorts the eigenvalues by magnitude from largest to smallest.

    'SM'

    Sorts the eigenvalues by magnitude from smallest to largest.

    'LR'

    Sorts the eigenvalues by real part from largest to smallest.

    'SR'

    Sorts the eigenvalues by real part from smallest to largest.

    'LI'

    Sorts the eigenvalues by imaginary part from largest to smallest.

    'SI'

    Sorts the eigenvalues by imaginary part from smallest to largest.

    Outputs

    ev

    Six eigenvalues of a or the generalized eigenvalues of a and b. ev is a vector.

    evec

    Matrix of six columns whose columns are the normalized eigenvectors of a or the normalized generalized eigenvectors of a and b.

    evdiag

    6-by-6 matrix with the elements of ev on the diagonal.

    Repeated Roots

    MathScript does not solve the off-diagonal Jordan structure associated with repeated roots. If repeated roots to eig(a) or eig(a, b) exist, MathScript might ill-condition evec artificially.

    A = rand(100);
    C = eigsort(A)

    Where This Node Can Run:

    Desktop OS: Windows

    FPGA: This product does not support FPGA devices


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