How do I do FFT for small amount of points?

1 view (last 30 days)
I have a small amount of data points X=[8 7 2 4 5 1] that I want to perform FFT for in order to find the trig functions that compose this repeating pattern. Is there an easy way to code this? I've seen a bunch of code that works for continuous samples of waves but I want to downsize it.

Answers (2)

Walter Roberson
Walter Roberson on 10 Dec 2016
fft(X)
is happy to work with small number of points

Joseph Schmidt
Joseph Schmidt on 10 Dec 2016
Ok I got the code to work but I'm not sure how to extract the frequency of the wave and amplitudes. Here is my code so far:
Fs = 1000; % Sampling frequency
T = 1/Fs; % Sampling period
L = 1000; % Length of signal
t = (0:L-1)*T; % Time vector
X = [2 2 1 0 0 1];
for i = 1:10
X = horzcat(X, X);
end
%plot(X);
Y = fft(X);
%plot(Y);
mag_Y = abs(Y)
plot(mag_Y);
  1 Comment
Walter Roberson
Walter Roberson on 10 Dec 2016
See the first example in the fft documentation as that shows how to label the x axis with frequency

Sign in to comment.

Categories

Find more on Fourier Analysis and Filtering in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!