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! Cholesky factorization: subroutine interface
program example_cholesky
use stdlib_linalg, only: cholesky
implicit none
real, dimension(3,3) :: A,L,U
! Set real matrix
A = reshape( [ [6, 15, 55], &
[15, 55, 225], &
[55, 225, 979] ], [3,3] )
! Decompose (lower)
call cholesky(A, L, lower=.true.)
! Compare decomposition
print *, maxval(abs(A-matmul(L,transpose(L))))
! Decompose (upper)
call cholesky(A, U, lower=.false.)
! Compare decomposition
print *, maxval(abs(A-matmul(transpose(U),U)))
end program example_cholesky
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