f = 1000;
Fs = 16000;
t = 0 : 1 / Fs : 0.005;
y = 2 * sin(2 * pi * f * t);
plot(t, y)

x = 1 : 1 : 10;
x = linspace(1, 10, 100);
c = ones(1, 10);
z = zeros(1,10);
y = [1 zeros(1, 39) 1];
stem(y)
axis([-0 42 -0.1 1.5])


normrnd