批量改高程值

将源代码粘贴到写字板里，后缀改为LSP：

;批量改高程值 gcbak
(defun c:gcbak()
(SETQ CZ (GETREAL"输入改正数:"))
(setq ent (ssget"x" '((8 . "GCD"))))
(if ent (progn
(setq long (sslength ent))
(setq num 0)
(repeat long
(setq ty (ssname ent num))
(setq data (entget ty))
(setq typ (cdr (assoc 0 data)))
(if (= "TEXT" TYP)
;(SETQ DATA (ENTGET (SETQ TY (CAR (ENTSEL)))))
(PROGN
(SETQ TEX (CDR (ASSOC 1 DATA)))
(SETQ TEX-NEW (+ CZ (ATOF TEX)))
(SETQ TEX-NEW (CONS 1 (RTOS TEX-NEW 2 2)))
(SETQ DA (SUBST TEX-NEW (ASSOC 1 DATA) DATA))
(ENTMOD DA)
)
(PROGN
(SETQ X (CADR (ASSOC 10 DATA))
Y (CADDR (ASSOC 10 DATA)))
(SETQ G (CADDDR (ASSOC 10 DATA)))
(SETQ G-NEW (+ CZ G))
(SETQ G-NEW (LIST 10 X Y G-NEW))
(SETQ DA (SUBST G-NEW (ASSOC 10 DATA) DATA))
(ENTMOD DA)
)
)
(setq num (1+ num))
);repeat
));if
);;;

<P><img src="images/post/smile/dvbbs/em01.gif" /><img src="images/post/smile/dvbbs/em02.gif" /><img src="images/post/smile/dvbbs/em05.gif" /><img src="images/post/smile/dvbbs/em06.gif" /><img src="images/post/smile/dvbbs/em07.gif" /><img src="images/post/smile/dvbbs/em08.gif" /><img src="images/post/smile/dvbbs/em22.gif" /><img src="images/post/smile/dvbbs/em23.gif" /><img src="images/post/smile/dvbbs/em24.gif" /><img src="images/post/smile/dvbbs/em37.gif" /></P><P>支持共享，感谢你的劳动！！</P>

能否说明在哪些情况下需要用？！