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<?xml-stylesheet type="text/xsl" href="../assets/xml/rss.xsl" media="all"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>gilgi.org (Posts about linear algebra)</title><link>https://gilgi.org/</link><description></description><atom:link href="https://gilgi.org/categories/linear-algebra.xml" rel="self" type="application/rss+xml"></atom:link><language>en</language><copyright>Contents © 2020 &lt;a href="mailto:site@gilgi.org"&gt;gilgi&lt;/a&gt; </copyright><lastBuildDate>Sat, 23 May 2020 20:33:03 GMT</lastBuildDate><generator>Nikola (getnikola.com)</generator><docs>http://blogs.law.harvard.edu/tech/rss</docs><item><title>First eigenvector vs principle component of a symmetric matrix </title><link>https://gilgi.org/blog/eigenvector/</link><dc:creator>gilgi</dc:creator><description>&lt;div class="cell border-box-sizing text_cell rendered"&gt;&lt;div class="prompt input_prompt"&gt;
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&lt;p&gt;Two concepts that are easy to confuse are &lt;a href="https://en.wikipedia.org/wiki/Eigenvalues_and_eigenvectors"&gt;eigenvectors&lt;/a&gt; and &lt;a href="https://en.wikipedia.org/wiki/Principal_component_analysis"&gt;principle components&lt;/a&gt;. When the matrix in question is symmetric, there is a relationship between the first eigenvector and the projection of the data onto its first principle component. In this post, we'll use &lt;a href="https://en.wikipedia.org/wiki/Diagonalizable_matrix#Diagonalization"&gt;diagonalization&lt;/a&gt; and &lt;a href="https://en.wikipedia.org/wiki/Singular_value_decomposition"&gt;singular value decomposition&lt;/a&gt; to try to shed some light on this.&lt;/p&gt;
&lt;p&gt;&lt;a href="https://colab.research.google.com/github/gilgi/gilgi.github.com/blob/src/posts/eigenvector.ipynb"&gt;&lt;img src="https://colab.research.google.com/assets/colab-badge.svg" alt="Open In Colab"&gt;&lt;/a&gt;&lt;/p&gt;
&lt;p&gt;&lt;a href="https://gilgi.org/blog/eigenvector/"&gt;Read more…&lt;/a&gt; (4 min remaining to read)&lt;/p&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;</description><category>linear algebra</category><category>notebook</category><category>Python</category><guid>https://gilgi.org/blog/eigenvector/</guid><pubDate>Sun, 13 Oct 2019 04:00:00 GMT</pubDate></item></channel></rss>