How can i solve?

Hello, I'm new to matlab. I kind of like it and i have a project at university based on matlab. I'm kind of bad at programming but i want to learn.

So i have the following exercise to solve:

I need to make a square signal on multiple levels.

The period of every signal is 0.25 s and i have the following levels:

a) {-1,1}

b) {-3,-1,1,3}

c) {-5,-3,-1,1,3,5}

d){-7,-5,-3,-1,1,3,5,7}

I m sorry if this aren't the rules of the website but i'm kind of desperate. If someone can solve the d) {-7,-5,-3,-1,1,3,5,7} so i can inspire from that.

[darova]

Can you make a simple drawing of result you expect?

[Liviu Iftime]

The problem says is the signal is random.

[Liviu Iftime]

t= 0:0.002:5;

n=125;% n=0.25/0.002

v=randn(1,20);k=1;s=[0 0];

for p=1:length(v)

if v(1,p)<0

v(1,p)=-1;

else v(1,p)=1;

end

end

for i=1:20

for j=1:125

s(1,k) = v(1,i);

k=k+1;

end

end

s(1,k)=v(1,i);

plot(t,s)

I have done this, and i think it s ok, but i m stucked at b)

[darova]

• I need to make a square signal on multiple levels.

What does it mean? HOw it should look like?

[Liviu Iftime]

[Liviu Iftime]

Answer 1

[Shubham Gupta]

Below code worked for me :

rng default
tsim = 0:0.002:10; % simulation time
Amp = {-7,-5,-3,-1,1,3,5,7}; % Amplitudes
dt = 0.25; % sample time
randAmp = [Amp{floor(length(Amp)*rand(tsim(end)/dt,1))'+1}]; % randomize amplitude over simulation time
func = @(t)0; % initialize function
for i = 1:length(randAmp)
func = @(t)func(t)+((t-dt*(i-1))*(t-(dt-1e-10)*i)<=0)*randAmp(i); % check where 't' lies and decide amplitude accordingly
end
plot(tsim,arrayfun(func,tsim)) % plot the results

Let me know if you have doubts !

[Liviu Iftime]

Well Thank you! I'm kind of confussed on what is that. I have managed to make myself the code and it has 140 lines. It's funny that you have in your code 10 lines, but as i said I have no ideea what is that code.

THANK YOU ANYWAYS!

[Shubham Gupta]

I am glad I could help. If you can tell me which part of the code you didn't understand, maybe I can help you understand in more detail. Also if it solves the problem for you, you can consider to accept the answer cheers !