Matrix pre-allocation question

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Jared
Jared on 19 Oct 2018
Edited: Matt J on 19 Oct 2018
I have attached an image of some code I'm working through. I have pre-allocated two matrices but MATLAB is still displaying the message suggesting I pre-allocate. I'm trying to determine whether it shows this message regardless of whether I've already done what it's asking me to do or not. My assumption was this message would disappear once I pre-allocated but that's not been the case.
  1 Comment
James Tursa
James Tursa on 19 Oct 2018
Please do not post code as images. Instead, post it as text and format it with the { } Code button.

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Accepted Answer

Matt J
Matt J on 19 Oct 2018
Edited: Matt J on 19 Oct 2018

It is true that you have pre-allocated, but (a) you still aren't using that pre-allocated space for anything, and (b) you are still using concatenation to make TBILL1Y grow with every pass through the loop. Your code should look something like,

count=0;
for i=...
 for j=...
       count=count+1;
       TBILL1Y(:,count)=DRAW(:,1);
   end
  end

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