[求助]：[0802]如何运用缩放达到需要的面积值?

xyz518mm

[求助]：[0802]如何运用缩放达到需要的面积值?
想要使用下面程序完成一个
选取物件后达到指定的面积值
但好像式计算方法错误了
烦请各位高手可以帮忙一下~
谢谢~


(defun c:ts ()
(setq nn (entsel "\n select:"))
(setq ea (car nn))
(setq ed (nth 1 nn))
(setq envla (la-to-vla ea))
(setq prarea (vlax-get envla 'area ))
(princ (strcat "\n 目前面积值:" (rtos prarea 2 2) ))
(setq tempobj (getreal "\n 需求面积值:"))
(setq scen (* (/ 1.0 prarea) tempobj))
(command "_.scale" ea "" ed scen)
(prin1))