test2.txt

编译原理的三个子模块,包括词法分析,语法分析和语义分析,是绘图语言解释器

--------------- 图形1：
origin is (20, 200);									-- 设置原点的偏移量
rot is 0;												-- 不旋转
scale is (40, 40);										-- 设置比例
for T from 0 to 2*pi+pi/50 step pi/50 draw (t, -sin(t));-- 画T的轨迹
origin is (20, 240);									-- 下移40单位
for T from 0 to 2*pi+pi/50 step pi/50 draw (t, -sin(t));-- 画T的轨迹
origin is (20, 280);									-- 再下移40单位
for T from 0 to 2*pi+pi/50 step pi/50 draw (t, -sin(t));-- 画T的轨迹

--------------- 图形2：
origin is (380, 240);									-- 右移
scale is (80, 80/3);									-- y方向压缩为三分之一
rot is pi/2+0*pi/3 ;									-- 旋转初值设置
for T from -pi to pi step pi/50 draw (cos(t), sin(t));	-- 画T的轨迹
rot is pi/2+2*pi/3;										-- 旋转2/3*pi
for T from -pi to pi step pi/50 draw (cos(t), sin(t));	-- 画T的轨迹
rot is pi/2-2*pi/3;										-- 再旋转2/3*pi
for T from -pi to pi step pi/50 draw (cos(t), sin(t));	-- 画T的轨迹

--------------- 图形3：
origin is(580, 240);									-- 再右移
scale is (80, 80);										-- 恢复原比例
rot is 0;												-- 不旋转
for t from 0 to 2*pi step pi/50 draw(cos(t),sin(t));	-- 画T的轨迹
for t from 0 to Pi*20 step Pi/50 draw					-- 画T的轨迹
   ((1-1/(10/7))*Cos(T)+1/(10/7)*Cos(-T*((10/7)-1)), 
	(1-1/(10/7))*Sin(T)+1/(10/7)*Sin(-T*((10/7)-1)));