Generalized Null Space Decomposition and Drazin Inverse

A MATLAB package to compute the Generalized Null Space Decomposition of a real or complex matrix (aka the Staircase Form), identifying the Jordan block structure for the zero eigenvalues of the matrix, along with its Drazin inverse.

The method is documented in this paper. The Drazin inverse is discussed in Appendix A.

GNSD code and required subroutines (written by G.W. Stewart)
Some auxiliary routines, not required by GNSD (written by M.L. Overton)
Routines to compute and verify the Drazin inverse (written by M.L. Overton)