n = 256;
t = 1:n;
noisey1 = rand(1,n);
noisey = noisey1 - mean(noisey1);
data = 0.1*sin(0.1*t);
total = noisey + data;
data2 = 0.2*sin(0.1*t + 10);
total2 = noisey + data2;
 dt = 0;
subplot(4,1,1);
plot(t,noisey,'o');
axis([0 n -1 1]);
subplot(4,1,2);
plot(t,data,'o');
axis([0 n -1 1]);
subplot(4,1,3);
plot(t,total,'o');
axis([0 n -1 1]);
subplot(4,1,4);
plot(t,total,'o',t,total2,'x');
axis([0 n -1 1]);