# How to calculate averaged values from 5-min interval values

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Daphne PARLIARI on 19 Sep 2019
Commented: Daphne PARLIARI on 31 Oct 2019
Hello guys.
I have the following question : I have observations for temperature in 5-minute interval, from 1/1/2015 to 31/1/2015 (8928 rows in total). From these data I must extract the hourly average value for temperature, which means that eventually I must have 24 hourly averaged values.
I would appreciate any ideas on the matter!
PS. I have attached the excel file I'm working on. Please note that the format of time appears diferently on Matlab.

David K. on 19 Sep 2019
Edited: David K. on 25 Sep 2019
Using for loops is a very straightforward way that this can be done:
size1 = length(x)/12;
size2 = 24;
sub1 = ones(size1,1); % intermediate matrix for averaging every hour
for n = 1:size1 % 8928/12 = 744
sub1(n) = mean(x(12*(n-1)+1 : (12*n))); % averages every 12 values to average every hour
end
hourlyVals = ones(size2 , 1); % 744/31 = 24
for n = 1:size2
hourlyVals(n) = mean(sub1(n:24:size1)); % calculate average of each hour across every day.
end
*edited to fix issue brought up in comments*
Daphne PARLIARI on 2 Oct 2019
If I delete the last 12 values in order to have all the days with 24 hourly values, then the shape of the diurnal variation of T is correct but the values are too low.
If I add again the last 12 values, the curve loses its shape but the hourly values are correct. It seems that I can't have it both ways.

Andrei Bobrov on 1 Oct 2019
Edited: Andrei Bobrov on 1 Oct 2019
T = T(~isnan(T.minute),[1:5,7:8]);
T.YEAR = str2double(T.YEAR);
T{:,{'AIR_TEMP_DegC','RH'}} = str2double(T{:,6:7});
T = T(:,[1:5,8:9]);
T_hour = varfun(@(x)mean(x,'omitnan'),T,'InputVariables',{'AIR_TEMP_DegC','RH'},'GroupingVariables','HOUR');
Daphne PARLIARI on 31 Oct 2019
Dear Andrei, I would like to ask a further question on your code which has worked dreamily.
Is there a way to create an intermediate matrix (before extracting the 24 hourly values of T) which will contain one hourly value of temperature for every hour of each day? With this, I need to have a temperature at 00.00 on 1/1/2015, temperature at 01.00 on 1/1/2015 and so on until 23.00 on 31/5/2015.
Is this applicable?

R2016a

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