.. _book_fig_chapter7_fig_spec_reconstruction:


PCA Reconstruction of a spectrum
--------------------------------
Figure 7.6

The reconstruction of a particular spectrum from its eigenvectors. The input
spectrum is shown in gray, and the partial reconstruction for progressively
more terms is shown in black. The top panel shows only the mean of the set of
spectra. By the time 20 PCA components are added, the reconstruction is very
close to the input, as indicated by the expected total variance of 94%.



.. image:: ../images/chapter7/fig_spec_reconstruction_1.png
    :scale: 100
    :align: center


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