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daily max -min , sum, average of hourly data sets.?

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pruth
pruth on 19 Oct 2016
Edited: pruth on 28 Oct 2016
hi,
I have created one mat file (attached). the first column is dates the second column is temperature- here I want to find daily max and min the third column is rainfall- here daily sum I don't need 4th and 5th column but for this time make an average.
in the date column, time is not given but it is an hourly data.(same date 24 times.)
i hope you understand

Accepted Answer

Andrei Bobrov
Andrei Bobrov on 20 Oct 2016
[y,m,d] = datevec(tempdata(:,1));
[a,~,c] = unique([y,m,d],'rows');
out = [a, zeros(size(a,1),7)];
out(:,4) = accumarray(c,tempdata(:,2),[],@nanmin);
out(:,5) = accumarray(c,tempdata(:,2),[],@nanmax);
out(:,6) = accumarray(c,tempdata(:,3),[],@nansum);
[ii,jj] = ndgrid(c,1:4);
out(:,7:10) = accumarray([ii(:),jj(:)],reshape(tempdata(:,4:7),[],1),[],@nanmean);
  2 Comments
pruth
pruth on 28 Oct 2016
sir, what shall I do if want repeats this process after every 3 column?
min max for the first column, the sum of the second column, mean for the third column,
and again action repeats . min max for the fourth column and so on...

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More Answers (1)

Steven Lord
Steven Lord on 19 Oct 2016
If you're using release R2016b or later, I recommend storing your data in a timetable and using the retime function to aggregate data over daily time bins as shown in the second example, "Aggregate Timetable Data and Calculate Mean Values", on that documentation page.
  1 Comment
pruth
pruth on 20 Oct 2016
hello steven , thanks for the reply,
I use R2013a.

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