conditional for loop not running

hey guys im having a problem running this code

the purpose is the anlyse a noisy signal data and find the time at which the signal reaches a percentage of the actual value

only the first conditional statement runs in the program , the other 2 wont even run

for i= 1:1:5079
    if(Y(i)<=90*L2_v/100)
        t90 = X(i);
    end
    if(Y(i)<=50*L2_v/100)
        t50 = X(i)
    end
    if(Y(i)<=10*L2_v/100)
        t10 = X(i);
    end
end

Answer 1

[KSSV]

% case 1 
idx = Y<=90*L2_v/100 ;
t90 = X(idx) ; 
% case 2 
idx = Y<=50*L2_v/100 ;
t50 = X(idx) ; 
% case 3 
idx = Y<=10*L2_v/100 ;
t10 = X(idx) ; 

[ali koulani]

i dont think i can use switch for this since all 3 cases can be valid at the same time

but i think i found the problem

[KSSV]

It is not a swtich. If you think there are values present which you gave, t90, t50, t10 will be calculated.