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Member of the linalgebra class.

Syntax

ev = eigs(a)

ev = eigs(a, b)

[evec, evdiag] = eigs(a)

[evec, evdiag] = eigs(a, b)

ev = eigs(a, order)

ev = eigs(a, b, order)

[evec, evdiag] = eigs(a, order)

[evec, evdiag] = eigs(a, b, order)

Description

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

Details

Examples

Inputs

Name	Description
a	Specifies a square matrix whose dependent matrices are also square.
b	Specifies a matrix of the same size as a. If you specify b, LabVIEW calls the qz function.
order	Specifies how to determine which eigenvalues and eigenvectors to compute. order is a string that accepts the following values. '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

Name	Description
ev	Returns six eigenvalues of a or the generalized eigenvalues of a and b. ev is a vector.
evec	Returns a matrix of six rows whose columns are the normalized eigenvectors of a or the normalized generalized eigenvectors of a and b.
evdiag	Returns a 6-by-6 matrix with the elements of ev on the diagonal.

Details

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

Examples

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

Related Topics

eig
qz