Exercise:PCA and Whitening
From Ufldl
(→Step 5: ZCA whitening) |
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=== Step 5: ZCA whitening === | === Step 5: ZCA whitening === | ||
| - | Now implement ZCA whitening to produce the matrix <math>x_{ZCAWhite}</math>. Visualize <math>x_{ZCAWhite}</math> and compare it to the raw data, <math>x</math>. You should observe that whitening results in, among other things, enhanced edges. Try | + | Now implement ZCA whitening to produce the matrix <math>x_{ZCAWhite}</math>. Visualize <math>x_{ZCAWhite}</math> and compare it to the raw data, <math>x</math>. You should observe that whitening results in, among other things, enhanced edges. Try repeating this with <tt>epsilon</tt> set to 1, 0.1, and 0.01, and see what you obtain. |
<table> | <table> | ||
