Mean Frequency ,Median Frequency ,Peak Frequency and Mean Power of an EMG signals

I have three EMG signals, I found Time Doamin Features like RMS,Mean,STD etc..of that signal.Now I wolud like to find its Frequecy Doamin Fatures of those signal.How do we use MATLAB functions to find those signal Featutes.

clc

close all

clear all

warning('off','all');

%% Import Data and plot te signal %%

[tm,signal1,Fs,labels]=rdmat('emg_healthy');

[tm,signal2,Fs,labels]=rdmat('emg_myopathy');

[tm,signal3,Fs,labels]=rdmat('emg_neuropathy');

samples=length(signal1);

figure(),subplot(311),plot(signal1),xlabel('No.of samples'),ylabel('Amplitude in mVolts')

title('Helathy Raw EMG data')

subplot(312),plot(signal2),xlabel('No.of samples'),ylabel('Amplitude in mVolts')

title('Myopathy EMG data')

subplot(313),plot(signal3),xlabel('No.of samples'),ylabel('Amplitude in mVolts')

title('Neuropathy EMG data')