Exercise:PCA and Whitening
From Ufldl
(→PCA, PCA whitening and ZCA implementation) |
(→PCA, PCA whitening and ZCA implementation) |
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== PCA, PCA whitening and ZCA implementation == | == PCA, PCA whitening and ZCA implementation == | ||
| - | In this problem set, you will implement PCA, PCA whitening and ZCA, as described in the lecture notes. | + | In this problem set, you will implement PCA, PCA whitening and ZCA whitening, as described in the lecture notes. |
| - | + | You will build on the MATLAB starter code which we have provided in <tt>..</tt>. You need only write code at the places indicated by "YOUR CODE HERE" in the files. The only file you need to modify is <tt>pca_gen.m</tt>. | |
=== Step 0: Load data === | === Step 0: Load data === | ||
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[[File:raw_images.png|240px|alt=Raw images|Raw images]] | [[File:raw_images.png|240px|alt=Raw images|Raw images]] | ||
| - | These patches are stored as column vectors <math>x^{(i)} \in \mathbb{R}^{196}</math> in the 196 | + | These patches are stored as column vectors <math>x^{(i)} \in \mathbb{R}^{196}</math> in the <math>196 \times 10000 matrix <math>x</math>. |
=== Step 1: Implement PCA === | === Step 1: Implement PCA === | ||
