PCA
From Ufldl
(→Example and Mathematical Background) |
(→Example and Mathematical Background) |
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can represent the data. Concretely, let <math>\textstyle x \in \Re^2</math> be some training example. Then <math>\textstyle u_1^Tx</math> | can represent the data. Concretely, let <math>\textstyle x \in \Re^2</math> be some training example. Then <math>\textstyle u_1^Tx</math> | ||
is the length (magnitude) of the projection of <math>\textstyle x</math> onto the vector <math>\textstyle u_1</math>. | is the length (magnitude) of the projection of <math>\textstyle x</math> onto the vector <math>\textstyle u_1</math>. | ||
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Similarly, <math>\textstyle u_2^Tx</math> is the magnitude of <math>\textstyle x</math> projected onto the vector <math>\textstyle u_2</math>. | Similarly, <math>\textstyle u_2^Tx</math> is the magnitude of <math>\textstyle x</math> projected onto the vector <math>\textstyle u_2</math>. | ||