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! Eigenvalues of a general real/complex matrix for the generalized eigenproblem
program example_eigvals_generalized
use stdlib_linalg, only: eigvals, eye
implicit none
real, allocatable :: A(:,:), B(:,:), lambda(:)
complex, allocatable :: cA(:,:), cB(:,:), clambda(:)
! NB Fortran is column-major -> transpose input
A = transpose(reshape([ [2, 8, 4], &
[1, 3, 5], &
[9, 5,-2] ], [3,3]))
B = eye(3)
! Real generalized eigenproblem
lambda = eigvals(A, B)
print *, 'Real generalized matrix eigenvalues: ', lambda
! Complex generalized eigenproblem
cA = cmplx(A, -2*A)
cB = cmplx(B, 0.5*B)
clambda = eigvals(cA, cB)
print *, 'Complex generalized matrix eigenvalues: ', clambda
end program example_eigvals_generalized
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