A method of diagonalizing Matrices using Jacobi Rotation Matrices. It consists of a sequence of Orthogonal Similarity Transformations, each of which eliminates one off-diagonal element.
See also Jacobi Algorithm, Jacobi Rotation Matrix
References
Press, W. H.; Flannery, B. P.; Teukolsky, S. A.; and Vetterling, W. T. ``Jacobi Transformation of a Symmetric Matrix.'' §11.1 in
Numerical Recipes in FORTRAN: The Art of Scientific Computing, 2nd ed. Cambridge, England:
Cambridge University Press, pp. 456-462, 1992.