How to create a vector?

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Sim 2012-10-16

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Hello everyone, Suppose with a for loop I get an array for each file (array could be of different lengths for each file). I want to get a column vector which will be merging of these arrays. So all the values of arrays from each file will be in this huge vector. Thank you for you help in advance.

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Answer 1

Babak 2012-10-16

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编辑：Babak 2012-10-16

在 MATLAB Online 中打开

 vector=[];
 for j=1:n
 % find newone that comes from file(j)
 vector = [vector , newone]
 end

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Sim 2012-10-16

Thank you veru much

Matt Kindig 2012-10-16

在 MATLAB Online 中打开

Keep in mind that if this is a "huge vector", then it might be rather slow due to a lack of memory pre-allocation. I would recommend something like this:

%  vector is output from file(j)
  r = size(vector,1);
  Vector = NaN(r,n);   %this is the pre-allocation step-- very important for memory management/efficiency!
  Vector(:,1)=vector;
  for j=2:n,
    %newone comes from file(j)
    Vector(:,j) = newone;
  end