# Extracting values that are greater than the threshold

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WILLBES BANDA on 28 Mar 2020
Commented: WILLBES BANDA on 28 Mar 2020
the Alert vector below is a combination of time in hours and minutes(column 1 and 2 respectively) and corresponding oxygen values (column 3). The threshold of oxygen is 21 and i want to store only values greater than 21 and their corresponding times in a (nx3) OxygenAlt vector. When i run the code below, i get the values of the unchanged Alert vector and they are not stored the way i want, please help.
Alert = 1.0000 12.0000 24.3687
2.0000 24.0000 19.3810
3.0000 36.0000 19.5573
4.0000 48.0000 18.9562
6.0000 0 22.3963
7.0000 12.0000 21.6010
8.0000 24.0000 22.6534
9.0000 36.0000 22.0820
10.0000 48.0000 21.1834
12.0000 0 19.5970
13.0000 12.0000 19.5775
14.0000 24.0000 23.5089
15.0000 36.0000 20.4282
16.0000 48.0000 20.8580
18.0000 0 23.5719
19.0000 12.0000 19.1469
20.0000 24.0000 20.9754
21.0000 36.0000 22.6969
when i run this code i get incorrect answers, please help
Alert = [OxygenTime Oxygen]
O = [Oxygen];
for Col = 1:1:length(Oxygen)
n = Alert(:,3)./21 ;
if n > 1
OxygenAlt = [Alert]
end
end
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### Accepted Answer

Peng Li on 28 Mar 2020
outAlert = Alert(Alert(:, 3) > 21, :);
should be what you want to have
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WILLBES BANDA on 28 Mar 2020
It works perfectly fine, Thank you very very much

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### More Answers (1)

Torsten on 28 Mar 2020
OxygenAlt = Alert(Alert(:,3)>21)
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WILLBES BANDA on 28 Mar 2020
It also works just fine, thank you very much

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