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Last change
on this file since 270 was 2, checked in by Rick van der Zwet, 15 years ago |
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Initial import of data of old repository ('data') worth keeping (e.g. tracking
means of URL access statistics)
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File size:
461 bytes
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| 1 | function Ak = approx(A, k)
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| 2 | % given matrix A and number k of top eigenvalues
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| 3 | % an approximation Ak is calculated via SVD
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| 4 | % k < m,n
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| 5 | [m, n] = size(A);
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| 6 | lo = m;
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| 7 | if ( n < m )
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| 8 | lo = n;
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| 9 | end
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| 10 | if ( lo < k )
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| 11 | k = lo;
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| 12 | end
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| 13 | [U, S, V] = svd(A);
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| 14 | svk = svds(A, k);
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| 15 | uk = U(:,[1:k]);
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| 16 | vk = V(:,[1:k]);
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| 17 | Ak = uk * diag(svk) * vk';
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| 18 | % plaatje is niet wenslijk in een functie, laten we erbuiten
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| 19 | % weergeven
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| 20 | % image(Ak);
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