a b/Ensemble Learning/AdaBoost/buildStump.m 

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function stump = buildStump(X, y, weight)





  
  

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D = size(X, 2); % Dimension





  
  

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if nargin <= 2





  
  

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    weight = ones(size(X,1), 1);





  
  

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end





  
  

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cellDS = cell(D, 1);





  
  

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Err = zeros(D, 1);





  
  

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for i = 1:D





  
  

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    cellDS{i} = buildOneDStump(X(:,i), y, i, weight);





  
  

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    Err(i) = cellDS{i}.error;





  
  

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end





  
  

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[v, idx] = min(Err);





  
  

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stump = cellDS{idx};





  
  

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end