Find maximum peaks in fft and power spectral density function

I have an array ( raw_acceleration) of 1600 elements acquired every 10 seconds at 160Hz from a sensor. I use this array to calculate the fft and the Power Spectral Density and it works very well:

Fs=160;
raw_acceleration = u;
N = length(raw_acceleration);
xdft = fft(raw_acceleration);
xdft = xdft(1:floor(N/2+1));
psdx = (1/(Fs*N)) * abs(xdft).^2;
psdx(2:end-1) = 2*psdx(2:end-1);
freq = 0:Fs/length(raw_acceleration):Fs/2;

plot(freq,10*log10(psdx))
grid on
xlabel('Frequency (Hz)')
ylabel('Power/Frequency (dB/Hz)')

I obtain this plot:

As you can see, I obtain four peaks centered around four different frequencies.

I would like to have a Matlab code which is able to automatically find these four maximum peaks and their frequency. At the moment, I always need to plot the graph and manually detect the maximum peak and its frequency.

Is there any way to do this by code? I hope you an help me.

I attached a sample of raw_acceleration array.

[Birdman]

Can you attach your original data?

Answer 1

[Birdman]

Use findpeaks function:

https://www.mathworks.com/help/signal/ref/findpeaks.html

[marcusbarnet]

I tried to use findpeaks function, but it gives me several peaks and not only a single value.

At the moment, I'm trying to use the max function by selecting intervals centered around the frequency (10Hz, 30 Hz, and so on) but it is not a good solution..

[Birdman]

Can you attach your original data?

[marcusbarnet]

Thank you for your support, I attached the files in the post below.

[Birdman]

marcusbarnet's answer moved here:

This is my raw_acceleration.mat array.

I attached also the freq and the psdx arrays.

Thank you for your help!

[marcusbarnet]

I attach also the freq array

[marcusbarnet]

I tried to use max() function in Matlab, but I found out that it doesn't work as I would like..