PCA
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= \sum_{i=1}^k u_i \tilde{x}_i. | = \sum_{i=1}^k u_i \tilde{x}_i. | ||
\end{align}</math> | \end{align}</math> | ||
- | The final equality above comes from the definition of <math>\textstyle U</math> [#Example and Mathematical Background|given earlier]. | + | The final equality above comes from the definition of <math>\textstyle U</math> [[#Example and Mathematical Background|given earlier]]. |
(In a practical implementation, we wouldn't actually zero pad <math>\textstyle \tilde{x}</math> and then multiply | (In a practical implementation, we wouldn't actually zero pad <math>\textstyle \tilde{x}</math> and then multiply | ||
by <math>\textstyle U</math>, since that would mean multiplying a lot of things by zeros; instead, we'd just | by <math>\textstyle U</math>, since that would mean multiplying a lot of things by zeros; instead, we'd just |