MATLAB: zvuk pro dechové cvičení

% zvuk pro dech
% ---------------
t_in = 4;
t_out = 4;
t_pause = 1;
duration = 60; % minutes
volume = 0.05;
% ---------------
fs = 8000;
f1 = 350;
f2 = 390;
t1 = 0:1/fs:t_in;
t2 = 0:1/fs:t_out;
t0 = 0:1/fs:1;
s1=linspace(f1,f2,length(t1));
s2=linspace(f2,f1,length(t2));
in = sin(2*pi*s1.*t1);
out = sin(2*pi*s2.*t2);
% play
y = [in t0 out t0];
y = repmat(y,1,duration*60/(t_in+t_pause+t_out+t_pause));
% sound(volume*y,fs);
audiowrite(['breath_excercise' num2str(duration) '.ogg'],volume*y,fs);