create an fft plot given f, n, l and y(x) in matlab

To create an FFT plot in MATLAB, you can first use the built-in fft function to find the Fourier transform of your signal. Then, you can use the abs function to get the magnitude of the Fourier coefficients. Finally, you can use the plot function to visualize the result.

Here's an example code snippet:

main.m
% Sample rate
f = 1000; % Hz
% Number of samples
n = 1024;
% Signal duration
l = n / f; % seconds

% Generate a test signal (in this case, a 50 Hz sine wave)
t = linspace(0, l, n);
x = sin(2*pi*50*t);

% Compute FFT and magnitude
y = fft(x);
mag = abs(y);

% Create frequency axis
f_axis = linspace(0, f, n);

% Plot FFT result
plot(f_axis, mag);
xlabel('Frequency (Hz)');
ylabel('Magnitude');
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This code will generate a sine wave at 50 Hz, compute its FFT using 1024 samples, and plot the magnitude of the Fourier coefficients as a function of frequency. You can modify the input signal as needed to analyze other types of signals.