MATLAB: How to average a matrix of 105108X6 constructed every 5 minutes measured data to 15 min

Question

Hello Matlab community,

I have a matrix (105108X6) of climate variables gathered every 5 minutes of one year, I wanna average this information every 15 minutes and store the info in a new matrix, how can I do that? I tried doing a loop like this:

dat_cal_15 = zeros(round(length(dat_cal)/3),1)
for i=1:round(length(dat_cal)/3)
    for a = 3*((i-1)+1)-2
        for b = 3*i
            dat_cal(i,1)= round(mean(dat_cal(a:b)));
        end
    end 
end

but is not working for all the columns….

thank you for your help

Answer 1

I's suggest using a timetable.

https://www.mathworks.com/help/matlab/timetables.html

Frist convert your matrix to timetable using array2timetable,

https://www.mathworks.com/help/matlab/ref/array2timetable.html

 dat_cal_TT = array2timetable(X,'RowTimes',time_column_here)

and then use retime,

https://www.mathworks.com/help/matlab/ref/retime.html

 TT_15min_mean = retime(dat_cal_TT,min_15_time_vector,'mean')

create a time vector (min_15_time_vector) with your desired sample time.