Abstract:
An n-by-n matrix is said to be totally nonnegative if
every minor of A is nonnegative. The problem of interest
is to characterize all possible Jordan canonical forms
(Jordan structures) of irreducible totally nonnegative
matrices. We demonstrate key relationships between the
number and sizes of the Jordan blocks corresponding
to zero and derive many relationships between all the
possible ranks and principal ranks of irreducible
totally nonnegative matrices. The main tools
used are the acyclic weighted diagrams (or digraphs)
associated with bidiagonal factorizations of totally
nonnegative matrices.