[求助]：怎么才能让小数点保留4位？

degucn

这个一个面积相除的程序，它能自动保留小数点后2位数，怎么才能让它保留小数点后4位数呢

(defun C:chu(/ oldos e1 e2 el1 el2 dat1 dat2 ans)
(setq olderr *error*)
(setq *error* myerr)
(setvar "cmdecho" 0)
(setq oldos (getvar "osmode"))
(setvar "osmode" 0)
(PRINC "\nPick the first number:")
(setq e1 (ENTSEL))
(princ "\nPick the second number:")
(setq e2 (ENTSEL))
(setq el1 (entget (car e1)) el2 (entget (car e2)))
(if (or (/=  "TEXT" (cdr (assoc 0 el1))) (/= "TEXT" (cdr (assoc 0 el2))))
   (progn
    (princ "\nYour choises not number, try again!")
    (exit)
   )
  )
(setq dat1 (cdr (assoc 1 el1)))
(setq dat2 (cdr (assoc 1 el2)))

;;;; divide

(setq ans (/ (atof dat1) (atof dat2)))
(setq ans (rtos ans 2 2))
;;;; write answer
(setq pt (getpoint "\nPick the point which answer to write:"))
(command "text" pt "" "" ans)
(setvar "osmode" oldos)
(setvar "cmdecho" 1)
(setq *error* olderr)
(princ)
)

xyp1964

(rtos ans 2 4)

Job_ho

(setvar "dimzin" 1) ;設定零值抑制模式為全部到指定的位數
這個很重要,如此就算尾數是0也會強迫顯示.