function [t,x] = sampling(freq_signal, sampling_freq, phase_signal, duration, plt)

%{
function [t,x] = sampling(freq_signal, sampling_freq, phase_signal, duration, plt)
ex: [t,x] = sampling(10,30,1,1)

Task: generate a cosine function knowing frequency, sampling freq, phase and duration

Inputs:
    -freq_signal: frequency of the signal (in hz)
    -sampling_freq: sampling frequency (how many sample per second) (in hz)
    -phase_signal: signal phase (in rad)
    -duration: how long u want the signal to be
    plt: if greater than 0, signal will be plotted 

Outputs:
    -t: time vector
    -x: amplitude of the cosine signal
    -a figure of a cosine signal

Author: Tikea TE 
Date: 11/04/2025
%}

% generate the time vector
t = -duration/2: 1/sampling_freq: duration/2;

% generate the cosine signal
x = cos(2*pi*freq_signal*t + phase_signal);

% plotting the figure 
if(plt)
    figure;
    plot(t,x,'b');
    xlabel('Time(s)');
    ylabel('signal amplitude(a.u.)');
    title(['cosine signal at ', num2str(freq_signal), 'Hz']); % use [] for joining string 
    grid on;
end