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! QR example with pre-allocated storage
program example_qr_space
use stdlib_linalg_constants, only: ilp
use stdlib_linalg, only: qr, qr_space, linalg_state_type
implicit none
real :: A(104, 32), Q(104,32), R(32,32)
real, allocatable :: work(:)
integer(ilp) :: lwork
type(linalg_state_type) :: err
! Create a random matrix
call random_number(A)
! Prepare QR workspace
call qr_space(A,lwork)
allocate(work(lwork))
! Compute its QR factorization (reduced)
call qr(A,Q,R,storage=work,err=err)
! Test factorization: Q*R = A
print *, maxval(abs(matmul(Q,R)-A))
print *, err%print()
end program example_qr_space
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