[LISP函数]：获取面积、惯性矩

mr.feng76

怎样用lisp获取面域的面积、惯性矩

xyp1964

2. [FONT=courier new];;;封闭域的形心、惯性矩、惯性积、旋转半径
   
3. (defun c:test285 ()
   
4.   (cmdlasc0)
   
5.   (setvar "osmode" 0)
   
6.   (mkla "中心线" 1)
   
7.   (while (setq pt (getpoint "\n选择区域内一点<退出> : "))
   
8.     (command "-boundary" "a" "o" "r" "" pt "")
   
9.     (setq s1 (entlast)
   
10.           pt (vlax-safearray->list
    
11.                (vlax-variant-value
    
12.                  (vla-get-centroid (vlax-ename->vla-object s1))
    
13.                )
    
14.              )
    
15.     )
    
16.     (XYP_SZX pt (* sc 100))
    
17.     (command "MASSPROP" s1 "" "y" "c:/tmp.mpr")
    
18.     (mkla "面域标注" 4)
    
19.     (write-tmp)
    
20.     (redraw)
    
21.   )
    
22.   (cmdla1)
    
23. )
    
24. (defun write-tmp ()
    
25.   (setq f (open "c:/tmp.mpr" "r"))
    
26.   (read-line f)
    
27.   (read-line f)
    
28.   (read-line f)
    
29.   (while (setq txt (read-line f))
    
30.     (setq pt (list (car pt) (- (cadr pt) (* sc 800))))
    
31.     (xyp-Text pt 1 txt)
    
32.   )
    
33.   (close f)
    
34. )
    
35. [/FONT]

[FONT=courier new];;;封闭域的形心、惯性矩、惯性积、旋转半径<br /> (defun c:test285 ()<br />   (cmdlasc0)<br />   (setvar "osmode" 0)<br />   (mkla "中心线" 1)<br />   (while (setq pt (getpoint "\n选择区域内一点<退出> : "))<br />     (command "-boundary" "a" "o" "r" "" pt "")<br />     (setq s1 (entlast)<br />           pt (vlax-safearray->list<br />                (vlax-variant-value<br />                  (vla-get-centroid (vlax-ename->vla-object s1))<br />                )<br />              )<br />     )<br />     (XYP_SZX pt (* sc 100))<br />     (command "MASSPROP" s1 "" "y" "c:/tmp.mpr")<br />     (mkla "面域标注" 4)<br />     (write-tmp)<br />     (redraw)<br />   )<br />   (cmdla1)<br /> )<br /> (defun write-tmp ()<br />   (setq f (open "c:/tmp.mpr" "r"))<br />   (read-line f)<br />   (read-line f)<br />   (read-line f)<br />   (while (setq txt (read-line f))<br />     (setq pt (list (car pt) (- (cadr pt) (* sc 800))))<br />     (xyp-Text pt 1 txt)<br />   )<br />   (close f)<br /> )<br /> [/FONT]