The Niblack–Nigam iterative method revisited

摘要

The iterative algorithm of Niblack and Nigam for matrix eigenvalues is derived in a simple manner and is improved so as to permit reliable numerical calculations. The computational capabilities of the algorithm are tested on a bound state problem and it is then shown how to extract eigenvector information from numerical eigenvalues. A complexified form of the algorithm is shown to permit the accurate calculation of complex resonant state energies.