MATLAB: How to write a LOOP for this case

for looploopvariablevariables

Hey all
I have 34 variable in my workplace like this:
precip_1982_daily
precip_1983_daily
precip_1984_daily
precip_1985_daily
…
precip_2015_daily
I want to use this if code below:
if size(precip_1982_daily,3)==365
    month_lengths=[31 28 31 30 31 30 31 31 30 31 30 31];%non-leap year
else
    month_lengths=[31 29 31 30 31 30 31 31 30 31 30 31];%leap year
end
precip_1982_monthly=mat2cell(precip_1982_daily,size(precip_1982_daily,1),size(precip_1982_daily,2),month_lengths);%divide into 1 cell per month
precip_1982_monthly=cellfun(@(x) nansum(x,3),precip_1982_monthly,'UniformOutput',false);%find mean for each month
precip_1982_monthly=cell2mat(precip_1982_monthly);%convert back to 3D array

Best Answer

So again, numbered variables and field names are a bad idea. (see here and here) for the related questions). The whole thing would be simpler if the original cell array was used.
If the original cell array had been kept, the code over the 3 questions could be simplified to:
%using original cell array precips
precip_monthly = cell(size(precips));  %preallocate result cell array
for idx = 1:numel(precips)
    if size(precips{idx}, 3) == 365
        month_lengths=[31 28 31 30 31 30 31 31 30 31 30 31];%non-leap year
    else
        month_lengths=[31 29 31 30 31 30 31 31 30 31 30 31];%leap year
    end
    p_month =mat2cell(precips{idx}, size(precips{idx}, 1), size(precips{idx}, 2), month_lengths);%divide into 1 cell per month
    p_month = cellfun(@(x) sum(x, 3, 'omitnan'), p_month, 'UniformOutput', false); %find mean for each month !!THIS CALCULATE THE SUM!!
    precip_monthly{idx} = cell2mat(p_month);%convert back to 3D array
end
Note that you have written a comment that says find mean for each month but you use the sum function. So either the code or the comment is wrong.
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