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Given a vector $x$ what are the eigenvectors of $\text{diag}(x) - xx^T$?

My observations so far:

  1. If we had only the first term, the matrix would already be diagonal.

  2. The second term, on the other hand, has a diagonal form with a single nonzero entry corresponding to the direction parallel to $x$

  3. This matrix acts on the vector $(1,1,\ldots,1)$ to yield a multiple of $x$.

  4. I also see how to invert the matrix using the Woodbury identity.

Kelly
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