Grip的CRVTRM怎么用(曲线裁剪)

ugman

各位大侠：菜鸟需用到Grip的CRVTRM命令，求助于此！！！十分感谢。
我要将ln3用c2和ln1裁剪，请教怎么写。

能找到的信息如下：
格式：
Obj=CRVTRM/curve,REF,{pt1|x,y,z},$
FIRST,limit1[,REF,{pt1|x,y,z}]$
[,INT,{pt2|x,y,z}][,NOTRIM]$
[,SECOND,limit2[,REF,{pt1|x,y,z}]][,INT,{pt2|x,y,z}][,NOTRIM]]$
,STATUS,status[,IFERR,label:]

ugman

$$Trim Curve Using Bounding Objects Example

ENTITY/SPLNP(4),SPLN,SPLNRS,ARC1P(3),ARC1,ARC2P(3),ARC2
ENTITY/LINE1P(2),LINE1,LINE2P(2),LINE2,LINE3P(2),LINE3
NUMBER/STAT

$$ CREATE LINES, ARCS, AND SPLINES TO TRIM

LINE1P(1) = POINT/-1,5,0
LINE1P(2) = POINT/-1,-1,0
LINE1 = LINE/LINE1P

LINE2P(1) = POINT/1,5,0
LINE2P(2) = POINT/1,-1,0
LINE2 = LINE/LINE2P

LINE3P(1) = POINT/-2,1,0
LINE3P(2) = POINT/2,1,0
LINE3 = LINE/LINE3P

SPLNP(1) = POINT/-2,2,0
SPLNP(2) = POINT/-0.5,2.5,0
SPLNP(3) = POINT/0.5,1.5,0
SPLNP(4) = POINT/2,2,0
SPLN = SPLINE/SPLNP

ARC1P(1) = POINT/2,4,0
ARC1P(2) = POINT/0,4.5,0
ARC1P(3) = POINT/-2,4,0
ARC1 = CIRCLE/ARC1P

ARC2P(1) = POINT/2,3,0
ARC2P(2) = POINT/0,3.5,0
ARC2P(3) = POINT/-2,3,0
ARC2 = CIRCLE/ARC2P

$$用LINE1剪去ARC1的右边

CRVTRM/ARC1,REF,ARC1P(2),FIRST,LINE1,INT,LINE1P(1),NOTRIM,STATUS,STAT,IFERR,ER1:

$$用LINE2剪去ARC2的左边

CRVTRM/ARC2,REF,ARC2P(2),FIRST,LINE2,INT,LINE2P(1),NOTRIM,STATUS,STAT,IFERR,ER1:

$$用LINE1、2剪去SPLIN的中间，是唯一产生另外线段SPLNRS的裁剪

SPLNRS=CRVTRM/SPLN,REF,SPLNP(2),FIRST,LINE1,INT,LINE1P(1),NOTRIM,$
SECOND,LINE2,INT,LINE2P(1),NOTRIM,STATUS,STAT,IFERR,ER1:

$$LINE1、2、3一起剪

CRVTRM/LINE3,REF,LINE3P(1),FIRST,LINE1,REF,LINE1P(2),$
SECOND,LINE2,REF,LINE2P(2),STATUS,STAT,IFERR,ER1:

JUMP/TERM:

ER1:
MESSG/'CRVTRM ERROR STATUS = ',ISTR(STAT)
TERM: HALT