PROGRAM newt
  IMPLICIT NONE
  REAL :: x = 0.0, d
  REAL, PARAMETER :: toleranssi = 1e3*EPSILON(x)
  INTEGER :: i, max_iter = 20
  WRITE (*,'(A,F9.6)') 'x:n arvo alussa:', x
  DO i = 1, max_iter
    d = (EXP(x) + x - 5)/(EXP(x) + 1)
    x = x - d
    WRITE (*,'(A,I3,A,F9.6)') 'i:', i, ', x:n arvo:', x
    IF (ABS(d) <= toleranssi*ABS(x)) EXIT
  END DO
END PROGRAM newt