In the vast ecosystem of numerical linear algebra, few texts command the respect and lasting relevance of Beresford Parlett’s "The Symmetric Eigenvalue Problem." Published by Prentice-Hall in 1980 (and reprinted by SIAM in 1998 as a "Classics in Applied Mathematics" edition), this monograph remains the definitive treatise on one of the most fundamental tasks in computational science: finding eigenvalues and eigenvectors of symmetric matrices.
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The Symmetric Eigenvalue Problem by Beresford N. Parlett is a foundational text in numerical linear algebra, originally published in 1980 and reissued by SIAM Publications parlett the symmetric eigenvalue problem pdf
Small to Medium Matrices: The first nine chapters focus on matrices where similarity transformations can be made explicitly, and the primary concern is the impact of inexact arithmetic. For only eigenvalues, step 2 suffices; for eigenvectors
Here's a write-up based on the book: