## How to make the Lanczos algorithm converge slowly

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- by D. S. Scott PDF
- Math. Comp.
**33**(1979), 239-247 Request permission

## Abstract:

The Paige style Lanczos algorithm is an iterative method for finding a few eigenvalues of large sparse symmetric matrices. Some beautiful relationships among the elements of the eigenvectors of a symmetric tridiagonal matrix are used to derive a perverse starting vector which delays convergence as long as possible. Why such slow convergence is never seen in practice is also examined.## References

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*Inverse Eigenvalue Problems for Banded Matrices*, Technical Report STAN-CS-77-623, Computer Science Department, Stanford University, 1977.

## Additional Information

- © Copyright 1979 American Mathematical Society
- Journal: Math. Comp.
**33**(1979), 239-247 - MSC: Primary 65F15
- DOI: https://doi.org/10.1090/S0025-5718-1979-0514821-5
- MathSciNet review: 514821