write the fft function without using the built in fft function and then plot the results in matlab

main.m
function Y = myFFT(X)
% Computes the FFT of the input signal X using the Cooley-Tukey algorithm

N = length(X);
halfN = N/2;
expo = -2i*pi/N;
W = exp(expo*(0:halfN-1));

if N == 1
    Y = X;
elseif mod(N,2) == 0
    X_even = myFFT(X(1:2:end));
    X_odd = myFFT(X(2:2:end));
    Y = [X_even+W.*X_odd X_even-W.*X_odd];
else
    X_even = myFFT(X(1:2:end-1));
    X_odd = myFFT(X(2:2:end));
    Y = [X_even+W.*X_odd X_even-W.*X_odd X_odd(end)];
end
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main.m
Fs = 1000;              % Sampling frequency
T = 1/Fs;               % Sampling period
L = length(Y);          % Length of signal
t = (0:L-1)*T;           % Time vector
f = Fs*(0:(L/2))/L;     % Frequency vector

figure
subplot(2,1,1)
plot(t,X)
axis([0 max(t) min(X) max(X)])
title('Time Domain Signal')
xlabel('Time (s)')
ylabel('Amplitude')

subplot(2,1,2)
plot(f,2*abs(Y(1:L/2+1)))
axis([0 max(f) 0 max(abs(Y))*2])
title('Frequency Domain Signal')
xlabel('Frequency (Hz)')
ylabel('Magnitude')
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