dm07401.m

the code of the book come form the book of marlix laboratory with the book of singal

%dm07401
%观察分析连续信号的时域运算
syms t 
f1=sym('Heaviside(t+2)-Heaviside(t-2)');
f2=sym('cos(2*pi*t)');
f3=f1+f2;                                 %两信号相加
f4=f1*f2;                                 %两信号相乘
subplot(2,2,1)
ezplot(f1,-5,5);
title('f1(t)=u(t+2)-u(t-2)')
axis([-5,5,-0.2,1.2])
subplot(2,2,2)
ezplot(f2);
title('f2(t)=(2*pi*t)')
subplot(2,2,3)
ezplot(f3);
title('f1(t)+f2(t)')
subplot(2,2,4)
ezplot(f4,-5,5);
title('f1(t)*f2(t)')
set(gcf,'color','w')