Merge pull request #3 from baptu123/patch-1

update the comments.

amplitude.m

@@ -1,30 +1,30 @@
 function am = amplitude
 
-Ac = input('Enter the value of carrier amplitude: ');
+Ac = input('Enter the value of carrier amplitude: ');    
 m = input('Enter the value of modulation index: ');
 fc = input('Enter the value of carrier frequency: ');
 fm = input('Enter the value of message signal frequency: ');
 
-Tfm = 1/fm;
-Tfc = 1/fc;
+Tfm = 1/fm;       % Time-period of message signal.
+Tfc = 1/fc;       % Time-eriod of carrier signal
 
 t1 = 0:Tfm/999:6*Tfm;
-t2 = 0:Tfc/999:6*Tfc;
+t2 = 0:Tfc/999:6*Tfc;   % while plotting carrier signal so that it is scaled to it's time period
 
-carrier_wave = Ac*sin(2*pi*fc*t2);
+carrier_wave = Ac*sin(2*pi*fc*t2);    % initializing the carrier wave and plotting it
 subplot(3,1,1)
 plot(t2, carrier_wave, 'r');
 title('carrier signal');
 
-message_wave = (Ac*m)*sin(2*pi*fm*t1);
+message_wave = (Ac*m)*sin(2*pi*fm*t1);    % initializing the message signal and plotting it.
 subplot(3,1,2)
 plot(t1, message_wave, 'b');
 title('Message Signal');
 
-am = Ac*(1+m.*sin(2*pi*fm*t1)).*sin(2*pi*fc*t1);
+am = Ac*(1+m.*sin(2*pi*fm*t1)).*sin(2*pi*fc*t1);    %initializing the amplitude modulated wave and plotting it.
 subplot(3,1,3)
 plot(t1, am, 'g');
 title('Amplitude Modulated Wave');
-grid on;
+grid on;      % turning the grid on so that it the values can be found out easily.
 
 end