7 citations · 12 across the 9 of their papers we have counts for
11 papers
The Karpelevič Region Revisited
Stephen Kirkland, Thomas Laffey, Helena Smigoc
We consider the Karpelevič region consisting of all eigenvalues of all stochastic matrices of order . We provide an alternative characterisation of $Θ_n…
Completely positive factorizations associated with Euclidean distance matrices corresponding to an arithmetic progression
Damjana Kokol Bukovšek, Thomas Laffey, Helena Šmigoc
Euclidean distance matrices corresponding to an arithmetic progression have rich spectral and structural properties. We exploit those properties to develop completely positive fact…
The integer cp-rank of matrices
Thomas Laffey, Helena Šmigoc
We show the cp-rank of an integer doubly nonnegative matrix does not exceed .
Diagonal realizability in the Nonnegative Inverse Eigenvalue Problem
Thomas J. Laffey, Helena Šmigoc
We show that if a list of nonzero complex numbers is the nonzero spectrum of a diagonalizable nonnegative matrix, then is the nonzero spectrum of a dia…
Integer completely positive matrices of order two
Thomas Laffey, Helena Šmigoc
We show that every integer doubly nonnegative matrix has an integer cp-factorization.
The diagonalizable nonnegative inverse eigenvalue problem
Anthony G Cronin, Thomas J Laffey
In this paper we prove that the SNIEP DNIEP, i.e. the symmetric and diagonalizable nonnegative inverse eigenvalue problems are different. We also show that the minimum …