.. _book_fig_chapter7_fig_eigenvalues:


SDSS Eigenvalues
----------------
Figure 7.5

The eigenvalues for the PCA decomposition of the SDSS spectra described in
Section 7.3.2. The top panel shows the decrease in eigenvalue as a function
of the number of eigenvectors, with a break in the distribution at ten
eigenvectors. The lower panel shows the cumulative sum of eigenvalues
normalized to unity. 94% of the variance in the SDSS spectra can be captured
using the first ten eigenvectors.



.. image:: ../images/chapter7/fig_eigenvalues_1.png
    :scale: 100
    :align: center


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