subplot(5,1,2);plot([101:200],s(101:200));axis([1 N min(s) max(s)]);grid on; subplot(5,1,3);plot([201:300],s(201:300));axis([1 N min(s) max(s)]);grid on; subplot(5,1,4);plot([301:400],s(301:400));axis([1 N min(s) max(s)]);grid on; subplot(5,1,5);plot([401:500],s(401:500));axis([1 N min(s) max(s)]);grid on; figure t=zeros(1,N/5); for i=1:num t=t+sin(f(i)*2*pi*(1:N/5)/f0+pi/2); end subplot(2,2,1);plot(t);axis([1 N min(s) max(s)]);grid on; t=zeros(1,N/5); for i=1:num t=t+sin(f(i)*2*pi*((N/5+1):(2*N/5))/f0+pi/2); end subplot(2,2,2);plot((N/5+1):(2*N/5),t);axis([1 N min(s) max(s)]);grid on; t=zeros(1,N/5); for i=1:num t=t+sin(f(i)*2*pi*((2*N/5+1):(3*N/5))/f0+pi/2); end subplot(2,2,3);plot((2*N/5+1):(3*N/5),t);axis([1 N min(s) max(s)]);grid on; t=zeros(1,N/5); for i=1:num t=t+sin(f(i)*2*pi*((3*N/5+1):(4*N/5))/f0+pi/2); end subplot(2,2,4);plot((3*N/5+1):(4*N/5),t);axis([1 N min(s) max(s)]);grid on; data0=rand(1,9999); %脑电信号原始数据 tm=0.02; %采样时间间隔 t=1:tm:10; %取时间 1-10 秒 data=data0(1:(10-1)/tm+1); %1-10 秒的数据 plot(t,data); xlabel('时间（秒）'),ylabel('脑波电压'),title('1-10s 脑电图波');