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