--- a
+++ b/Ensemble Learning/AdaBoost/buildStump.m
@@ -0,0 +1,16 @@
+function stump = buildStump(X, y, weight)
+D = size(X, 2); % Dimension
+
+if nargin <= 2
+    weight = ones(size(X,1), 1);
+end
+
+cellDS = cell(D, 1);
+Err = zeros(D, 1);
+for i = 1:D
+    cellDS{i} = buildOneDStump(X(:,i), y, i, weight);
+    Err(i) = cellDS{i}.error;
+end
+[v, idx] = min(Err);
+stump = cellDS{idx};
+end