Need help to see if the two codes I fused together are correctly placed

clear all; close all;

a = arduino('/dev/tty.SLAB_USBtoUART', 'uno')

tic

max_samples = 1000;

tic 

for i = 1:max_samples
    sound_data(i) = readVoltage(a,'A2')
    time_data(i) = toc;
end

plot(time_data, sound_data)

figure
h = animatedline;
ax = gca;
ax.YGrid = 'on';
ax.YLim = [-0.1 5];
title('Sound sensor voltage vs time (live)');
ylabel('Time [HH:MM:SS]');
xlabel('Voltage [volt]');


stop = false;
startTime = datetime('now'); 
while ~stop
voltage = readVoltage(a,'A2');


t = datetime('now') - startTime;
addpoints(h,datenum(t),voltage)
ax.XLim = datenum([t-seconds(15) t]);
datetick('x','keeplimits')
drawnow
stop = readDigitalPin(a,'D6');
end