36 lines
1.1 KiB
Matlab
36 lines
1.1 KiB
Matlab
function X_rec = recoverData(Z, U, K)
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%RECOVERDATA Recovers an approximation of the original data when using the
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%projected data
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% X_rec = RECOVERDATA(Z, U, K) recovers an approximation the
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% original data that has been reduced to K dimensions. It returns the
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% approximate reconstruction in X_rec.
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%
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% You need to return the following variables correctly.
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X_rec = zeros(size(Z, 1), size(U, 1));
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m = rows(Z);
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n = size(U, 1);
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% ====================== YOUR CODE HERE ======================
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% Instructions: Compute the approximation of the data by projecting back
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% onto the original space using the top K eigenvectors in U.
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%
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% For the i-th example Z(i,:), the (approximate)
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% recovered data for dimension j is given as follows:
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% v = Z(i, :)';
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% recovered_j = v' * U(j, 1:K)';
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%
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% Notice that U(j, 1:K) is a row vector.
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%
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for i = 1:m
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for j = 1:n
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v = Z(i, :)';
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X_rec(i,j) = v' * U(j, 1:K)';
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endfor
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endfor
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% =============================================================
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end
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