clc;
clear;
close;
t=linspace(0,1,1000);
f=1;
m=0.5+0.5*cos(2*%pi*f*t);
subplot(2,1,1);
plot(t,m);

title('message signal');
val_min=min(m);
val_max=max(m);
temp=input('enter number of bits');
ma=2^temp;
va=linspace(val_min,val_max,ma);
pcm_val=zeros(1,length(m));
pcm_val(m<=(va(2)/2))=va(1);
for i=2:(ma-1)
    pcm_val(m>((va(i-1)+va(i))/2)&(m<=(va(i)+va(i+1))/2))=va(i);
end
pcm_val(m>((va(ma-1)+va(ma))/2))=va(ma);

subplot(2,1,2);
plot(t,pcm_val);

title('pulse code modulation');