How to plot a function of multiple variables, where only 1 variable is unknown

Hello,

I am trying to look into hilbert transforms for my class. I am fairly new to matlab so I am experiencing some trouble trying to plot these functions.

Below is some code for a raisedCosine sqrt funciton (IIR) and I am trying to plot this as a function of t with specified values of tau, T_b, and alpha. When I run this code I get the picture below, which is essentially nothing. Am I coding this correctly? I was not able to find alot of support on this exact question.

[Pooja Kumari]

Can you provide the code not in the screenshot format?

[GRANT]

syms t
fplot(raisedCosineSqrt(t, 0.3e-6, 1e-6, 0.25), [-100 100])
ylim([-10 10])
syms test
test = raisedCosineSqrt(t, 0.3e-6, 1e-6, 0.25)

syms f omega convolution
f = raisedCosineSqrt(t, 0.3e-6, 1e-6, 0.25) * raisedCosineSqrt(t-omega, 0.3e-6, 1e-6, 0.25);
f
convolution = int(f, -inf, inf);


function rc_sq_t = raisedCosineSqrt(t, tau, T_b, alpha)
    rc_sq_t = (1/sqrt(T_b))*((sin((1-alpha)*(pi*t/T_b))+(4*alpha*t/T_b)*(cos((1+alpha)*pi*t/T_b)))/((pi*t/T_b)*(1-(4*alpha*t/T_b)^2)));
end

[GRANT]

Added some extra to it for testing purposes. Trying to debug this right now.

Answer 1

[Pooja Kumari]

Dear GRANT,

I understand that you are facing issues when plotting the raisedCosine square root function (IIR) as a function of 't', using specified values of 'tau', 'T_b', and 'alpha'. Instead of creating a separate function to obtain the output of the raisedCosine square root function, you can directly store the output in a variable called 'rc_sq_t'. I have provided a sample code below for reference:

% Define the symbolic variable
syms t
tau =0.3e-6;
T_b = 1e-6;
alpha = 0.25;

% Define the function
rc_sq_t = (1/sqrt(T_b))*((sin((1-alpha)*(pi*t/T_b))+(4*alpha*t/T_b)*(cos((1+alpha)*pi*t/T_b)))/((pi*t/T_b)*(1-(4*alpha*t/T_b)^2)));

% Plot the function
fplot(rc_sq_t,[-100,100])

You can refer to the below documentation for more information on "fplot" function:

https://in.mathworks.com/help/matlab/ref/fplot.html

I hope this helps!