How to output a variable from a loop as a large array

Question

Josh 2012-7-12

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I'm hoping to output the variable 'fluxset' from a loop into an array which would store all the outputs into one large array.

I have tried a fluxset(month)=... array storage method to no luck, I also tried outputting the variable as a series of .mat files using the sprintf function to name the files however the variable names were all the same and I could not fix this issue due to a supposed 'dynamic variable naming' issue.

My code is approx. in the form:

           for year=[1993:2007]
                 for month=[1:12]
                 ...
                 fluxset=[fluxa;fluxb;fluxc]
                 end
           end

I hope to either store an all loop outputs array or alternatively a year by year output array.

If anyone could help, I would be greatly appreciative.

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Josh 2012-7-12

fluxa... are all 1x1, so subsequently fluxset is 3x1

Conrad 2012-7-12

在 MATLAB Online 中打开

Could try:

years = 1993:2007;
months = 1:12;
fluxset = zeros(numel(years),numel(months),3);
for year = years
    for month = months
       fluxset(year-years(1)+1,month-months(1)+1,:) = [1 1 1]';
    end
end

Note that I used dummy values [1 1 1]' in place of [fluxa;fluxb;fluxc].

Conrad

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Answer 1

Michelle 2012-7-12

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If I understand you right - I THINK you want the information from each loop to be added on to the array right? If so, this could work but creating a different variable - one that gets recomputed with each loop, adn then the "master" variable that gets the recomputed varible added on to it with each loop:

fluxset = [];  
   for year=[1993:2007]
        for month=[1:12]
        fluxset0=...%Computations here;
        fluxset = [fluxset; fluxset0];
    end

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Josh 2012-7-13

Thank you Michelle and all who have assisted, you've saved me hours of mind-numbing file editing.

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Answer 2

Jan 2012-7-12

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And with the important pre-allocation:

n = (2007 - 1993 + 1) * 12;
fluxset = zeros(n, 3);  % Pre-allocate!
index = 0;
for year = 1993:2007
  for month=[1:12]
     ...
     index = index + 1;
     fluxset(index, :) = [fluxa, fluxb, fluxc];
  end
end