How to add data stored in structure depending on other data related but stored in a different structure

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Cybelus
Cybelus 2023-6-2
评论： Stephen23 2023-6-9
Hi people!
I have some streamflow data that are stored in a structure called 'debit' (1x78888). Each streamflow data are related to a date and time (dd-MM-yyyy HH:mm:ss), which are stored in an other structure called 'Date' (1x78888). I want to have a mean streamflow per day. So what I did, is that I copied all the dates but without the hours to have data like 'dd-MM-yyyy'. Then I tried to do a while loop to sum all streams for a same day.
So far, my script looks like bellow, but it doesn't works. All I have in my structure called 'debit_total' are zeros...
Can someone help me with this ?
I hope it is clear enough !
load DE5.mat;
debit = Data.raw.horaire.debits;
date = Data.raw.horaire.time;
date.Format = 'dd-MMM-yyyy';
date_jour = date;
debit_total = zeros(size(debit));
i = 1;
while i <= length(date_jour)
if date_jour(i) == date_jour(i+1)
debit_total(i) = debit(i) + debit(i+1);
debit_total(i+1) = debit(i) + debit(i+1);
end
i = i + 1;
end

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chicken vector
chicken vector 2023-6-2
编辑：chicken vector 2023-6-2
Ran in:
I am not sure I udnerstand correctly what you need, because this line is confusing me:
debit_total = zeros(size(debit));
You want the average per day but you initialise the output with the same number of elements of every time instant.
Is something like this close to what you are looking for?
% Create fictitious data:
N = 5e3;
totDays = 40;
debit = randi(1e2, 1, N);
date = linspace(datetime('now'), ...
(datetime('now') + days(totDays)), ...
N) - years(1);
% Find of unique dates:
[y, m, d] = ymd(date);
[~, idx] = unique([y', m', d'], 'Rows', 'Stable');
uniqueDays = date(idx);
% Loop over each unique day:
meanDebit = zeros(size(uniqueDays));
for j = 1 : length(uniqueDays)
% Find all debits corresponding to the same [day, month, year]_
meanDebit(j) = mean(debit( day(date) == day(uniqueDays(j)) ...
& month(date) == month(uniqueDays(j)) ...
& year(date) == year(uniqueDays(j)) ));
% If timespan is less than a year you can compare only days and months:
% meanDebit(j) = mean(debit( day(date) == day(uniqueDays(j)) ...
% & month(date) == month(uniqueDays(j)) );
% If timespan is less than a month you can compre only days:
% meanDebit(j) = mean(debit( day(date) == day(uniqueDays(j)) ));
end
% Display result:
uniqueDays.Format = 'dd-MMM-yyyy';
table(uniqueDays', meanDebit', 'VariableNames', {'Date', 'Average Debit'})
output = 41×2 table
Date Average Debit ___________ _____________ 02-Jun-2022 49.459 03-Jun-2022 47.472 04-Jun-2022 48.456 05-Jun-2022 52.528 06-Jun-2022 51.272 07-Jun-2022 56.096 08-Jun-2022 53.712 09-Jun-2022 51.016 10-Jun-2022 48.336 11-Jun-2022 51.976 12-Jun-2022 51.312 13-Jun-2022 54.032 14-Jun-2022 50.472 15-Jun-2022 52.984 16-Jun-2022 53.8 17-Jun-2022 51.12

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