csv data to fft in matlab

this 1_20mhz.csv data is time domain signal

one of vector means time and the last one is Voltage of the signal

i want to change this csv data to fft in matlab

(time, voltage) -> (frequency , magnitude)

Answer 1

[Chunru]

x = readmatrix("1_20mhz.csv");
n = size(x, 1);
fs = 1/diff(x(1:2))         % sampling frequency

fs = 5.0000e+07

y = fft(x(:,2));
f = (0:n-1)/n*fs;

%plot(f, abs(y))
plot(f/1e6, 20*log10(abs(y)))
xlabel('f(MHz)'); ylabel('Amp (dB)'); grid on
xlim([1.9 20])

[Kyong Sun Bae]

thank you very much, but i have a question.

the csv file '1_20mhz' is from analog discovery2 at digilent, and the fft graph of the 1_20mhz is that png file.

your answer and below photo is different.

[Chunru]

Use the log scale for amplitude and use the comparable xlim to achieve the similar result. See the updated answer above.

[Kyong Sun Bae]

holy moly i love you so much!! thank you very much

[Kyong Sun Bae]

but i want to before answer that you replied

can you bring me the code that you replied first at my question?