t=-2*pi:pi/10:2*pi;

y=sin(t)./t;

tt=t+(t==0)*eps;

yy=sin(tt)./tt;

subplot(1,2,1),plot(t,y),axis([-7,7,-0.5,1.2]),

xlabel('t'),ylabel('y'),title('残缺图形')

subplot(1,2,2),plot(tt,yy),axis([-7,7,-0.5,1.2])

xlabel('t'),ylabel('yy'),title('正确图形')  

Warning: Divide by zero.

图2.13-1 极限处理前后的图形对照

2.13.2                       逻辑操作