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matlabplotcomponentsfrequencypolynomials

How to plot a polynomials

I'm trying to plot these polynomials shown in the image, but I keep receiving errors, and I'm not if my code is correct or not. Could you please help? Regards

Polynomials: polynomials

CODE:

clear all
close all
clc
%%

Fs = 1000;                    % Sampling frequency
T = 1/Fs;                     % Sampling period
L = 1024;                     % Length of signal
t = 2*(0:L-1)*T;               % Time vector
x = 0;
c = 1+i;

P(1) = 1;
Q(1) = 1;
P(2) = P(1) + exp(i*(2^(0))*t)*Q(1);
Q(2) = P(1) - exp(i*(2^(0))*t)*Q(1);
P(3) = P(2) + exp(i*(2^(1))*t)*Q(2);
Q(3) = P(2) - exp(i*(2^(1))*t)*Q(2);
P(4) = P(3) + exp(i*(2^(2))*t)*Q(3);
Q(4) = P(3) - exp(i*(2^(2))*t)*Q(3);

for m=1:16
    x = x +c*exp(i*2*pi*m*t).*P(m);
end

figure
subplot(2,2,1)
plot(t,P(3))
title('signal')
Solution

  • Here's a quick fix to your code as written.

    clear all
close all
clc
%%

Fs = 1000;                    % Sampling frequency
T = 1/Fs;                     % Sampling period
L = 1024;                     % Length of signal
t = 2*(0:L-1)*T;               % Time vector
x = zeros(1,L);
c = 1+1i;

P = zeros(16,L); Q= zeros(16,L);

P(1,:) = 1;
Q(1,:) = 1;
for j = 1:16
    P(j+1,:) = P(j,:) + exp(1i*(2^j)*t).*Q(j,:);
    Q(j+1,:) = P(j,:) - exp(1i*(2^j)*t).*Q(j,:);
end

for m=1:16
    x = x +c*exp(i*2*pi*m*t).*P(m,:);
end

figure
subplot(2,2,1)
plot(t,P(3,:))
title('signal')