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! Matrix pseudo-inversion example: function, subroutine, and operator interfaces
program example_pseudoinverse
use stdlib_linalg, only: pinv, pseudoinvert, operator(.pinv.), linalg_state_type
implicit none
real :: A(15,5), Am1(5,15)
type(linalg_state_type) :: state
! Generate random matrix A (15x15)
call random_number(A)
! Pseudo-inverse: Function interfcae
Am1 = pinv(A, err=state)
print *, 'Max error (function) : ', maxval(abs(A-matmul(A, matmul(Am1,A))))
! User threshold
Am1 = pinv(A, rtol=0.001, err=state)
print *, 'Max error (rtol=0.001): ', maxval(abs(A-matmul(A, matmul(Am1,A))))
! Pseudo-inverse: Subroutine interface
call pseudoinvert(A, Am1, err=state)
print *, 'Max error (subroutine): ', maxval(abs(A-matmul(A, matmul(Am1,A))))
! Operator interface
Am1 = .pinv.A
print *, 'Max error (operator) : ', maxval(abs(A-matmul(A, matmul(Am1,A))))
end program example_pseudoinverse
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