48 lines
1.3 KiB
Matlab
48 lines
1.3 KiB
Matlab
function idx = findClosestCentroids(X, centroids)
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%FINDCLOSESTCENTROIDS computes the centroid memberships for every example
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% idx = FINDCLOSESTCENTROIDS (X, centroids) returns the closest centroids
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% in idx for a dataset X where each row is a single example. idx = m x 1
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% vector of centroid assignments (i.e. each entry in range [1..K])
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%
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% Set K
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K = size(centroids, 1);
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m = rows(X);
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% You need to return the following variables correctly.
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idx = zeros(size(X,1), 1);
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% ====================== YOUR CODE HERE ======================
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% Instructions: Go over every example, find its closest centroid, and store
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% the index inside idx at the appropriate location.
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% Concretely, idx(i) should contain the index of the centroid
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% closest to example i. Hence, it should be a value in the
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% range 1..K
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%
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% Note: You can use a for-loop over the examples to compute this.
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%
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for i = 1:m
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tempX = X(i,:);
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tempSums = zeros(K,1);
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for j = 1:K
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tempCentroid = centroids(j,:);
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tempDiff = tempX - tempCentroid;
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tempDiff = tempDiff.^2;
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tempSums(j) = sum(tempDiff);
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endfor
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[minimum, temp_idx] = min(tempSums);
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idx(i) = temp_idx;
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endfor
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% =============================================================
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end
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