折线图4-绘制曲边矩形
a=滑动条(0,5,0.01)
赋值(a,1)
b=滑动条(0,5,0.01)
赋值(b,1)
r=滑动条(0,5,0.01)
赋值(r,1)
A=(-a,-b)
B=(a,-b)
C=(a,b)
D=(-a,b)
l1={A,A,B,B,C,C,D,D,A}
l2=x(l1)
l3=y(l1)
l4={-pi,-pi/2,-pi/2,0,0,pi/2,pi/2,pi,pi}
f(x)=折线图{0...8,l2)
g(x)=折线图{0...8,l3)
h(x)=折线图{0...8,l4)
a=曲线((f(t),g(t))+(r;h(t)),t,0,8)