(define (make-liste buffer i)
      (cond ((<= i (- (length times) 1)) (make-liste (append buffer (make-posn (+ (abs minn) (/ 500 (length times)) (car (list-ref times i))) 0)) (+ i 1)))
            (else (maxtime minn maxn (reverse buffer)))))
    (make-liste '() 0)
    )