How can I plot a comb function?

Hello,

A comb function is an array of delta functions spaced equally. I want to plot a function like this. F(x)= comb(2x)*sinc(50x).sinc^2(x). I could manage the sinc and the sinc^2. But I don't understand how I can plot the comb function which is a summation of deltas from -inf to +inf

Answer 1

[Wayne King]

You can simply create a discrete-time (Kronecker delta) impulse and repeat that. For example:

 x = 0:(2*pi)/1000:pi-(2*pi)/1000;
 diraccomb = zeros(size(x));
 diraccomb(1) = 1;
 diraccomb = repmat(diraccomb,1,10);
 xnew = 0:(2*pi)/1000:(5000*(2*pi)/1000)-(2*pi)/1000;

The above is a Dirac comb spaced at pi. You can easily modify for any sampling grid or period.

Answer 2

[Image Analyst]

You can use stem() to make a plot that looks like a comb function. See the help.

stem(ones(1,10), 'LineWidth', 2)
ylim([0, 2]);

Answer 3

[Pavan Kumar]

Hii Wayne..

I want to plot the comb function but unable to do so..

Could you send me the code for it.

Thanking you

Answer 4

[Li]

%Hi, Poonam, maybe you can try this one, too.

clc

clear all

numx = 501;

xmax = 5;

x = linspace(-xmax,xmax,numx);

Delta_X = 0.8;

% sample_x = abs(rem(x,1)); sample = zeros(1,numx);

for j=1:numx

R = abs(rem(x(j)+xmax,Delta_X));

if R == 0;

sample(j) = 1; % the amplitude can be adjusted

end

end

plot(x,sample)

axis tight

Answer 5

[suketu vaidya]

function taska

h = 1;

x = -pi:0.01:pi;

d = 50;

y0 = -1;

c1=(y0-(d^2/(d^2+1)));

y=@(x)c1*exp(-diff(x))+d*(sin(x)/(d^2+1))+d^2*(cos(x)/d^2+1);

plot(x,y(x));

end

i am not able to plot this graph