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! Eigendecomposition of a real square matrix
program example_eig
use stdlib_linalg, only: eig
implicit none
integer :: i
real, allocatable :: A(:,:)
complex, allocatable :: lambda(:),vectors(:,:)
! Decomposition of this square matrix
! NB Fortran is column-major -> transpose input
A = transpose(reshape( [ [2, 2, 4], &
[1, 3, 5], &
[2, 3, 4] ], [3,3] ))
! Get eigenvalues and right eigenvectors
allocate(lambda(3),vectors(3,3))
call eig(A, lambda, right=vectors)
do i=1,3
print *, 'eigenvalue ',i,': ',lambda(i)
print *, 'eigenvector ',i,': ',vectors(:,i)
end do
end program example_eig
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