According to my understanding of the issue, you want your sensors to light up as "green" or "red" based on some specific conditions for instance if "C3" is the greatest value in a particular interval say "1-15" then the "Lamp3" will become "red" but if "B3" is the greatest then "Lamp4" will become "red". If this is what you were trying to achieve then according to the code provided by you, I only see one condition in the interval "1-15" in which if "C3" is the greatest value then your code will work fine and "Lamp3" will become "red" but if that is not the case then nothing will happen for that duration i.e., "1-15" and all lamps will remain "green" in that duration, same issue with all other durations "30-45" and "45-60".
I would recommend that you put all your conditions inside a function and call that function which checks for all the appropriate conditions and lights up the lamp which satisfies the correct condition. As an example, look at the below code snippet.
A3 = 5-(5+5)*rand(60,1);
B3 = 5-(5+5)*rand(60,1);
C3 = 5-(5+5)*rand(60,1);
LamptoLight(A3,B3, C3, 1, 15);
LamptoLight(A3,B3, C3, 15, 30);
LamptoLight(A3,B3, C3, 30, 45);
LamptoLight(A3,B3, C3, 45, 60);
function LamptoLight(A3, B3, C3, from, to)
Lamp1 = 'green';
Lamp2 = 'green';
Lamp3 = 'green';
Lamp4 = 'green';
if ((abs(mean(C3(from:to)))>abs(mean(B3(from:to)))) && (abs(mean(C3(from:to)))>abs(mean(A3(from:to)))))
Lamp1 = 'green';
Lamp2 = 'green';
Lamp3 = 'red';
Lamp4 = 'green';
elseif ((abs(mean(B3(from:to)))>abs(mean(C3(from:to)))) && (abs(mean(B3(from:to)))>abs(mean(A3(from:to)))))
Lamp1 = 'green';
Lamp2 = 'green';
Lamp3 = 'red';
Lamp4 = 'green';
elseif ((abs(mean(A3(from:to)))>abs(mean(B3(from:to)))) && (abs(mean(B3(from:to)))>abs(mean(C3(from:to)))))
Lamp1 = 'green';
Lamp2 = 'red';
Lamp3 = 'green';
Lamp4 = 'green';
elseif ((abs(mean(A3(from:to)))>abs(mean(C3(from:to)))) && (abs(mean(C3(from:to)))>abs(mean(B3(from:to)))))
Lamp1 = 'red';
Lamp2 = 'green';
Lamp3 = 'green';
Lamp4 = 'green';
end
disp("From "+from+" to: "+to );
disp("Lamp1: "+Lamp1);
disp("Lamp2: "+Lamp2);
disp("Lamp3: "+Lamp3);
disp("Lamp4: "+Lamp4);
end
