1 citations · 2 across the 4 of their papers we have counts for
7 papers
Factorization of CP-rank-3 completely positive matrices
Jan Brandts, Michal Krizek
A symmetric positive semi-definite matrix A is called completely positive if there exists a matrix B with nonnegative entries such that A=BB^T. If B is such a matrix with a minimal…
On the combinatorial structure of 0/1-matrices representing nonobtuse simplices
Jan Brandts, Apo Cihangir
A 0/1-simplex is the convex hull of n+1 affinely independent vertices of the unit n-cube I^n. It is nonobtuse if none its dihedral angles is obtuse, and acute if additionally none…
Enumeration and investigation of acute 0/1-simplices modulo the action of the hyperoctahedral group
Jan Brandts, Apo Cihangir
The convex hull of n+1 affinely independent vertices of the unit n-cube Cn is called a 0/1-simplex. It is nonobtuse if none its dihedral angles is obtuse, and acute if additionally…
Geometric aspects of the symmetric inverse M-matrix problem
Jan Brandts, Apo Cihangir
We investigate the symmetric inverse M-matrix problem from a geometric perspective. The central question in this geometric context is, which conditions on the k-dimensional facets…
There are only two nonobtuse binary triangulations of the unit -cube
Jan Brandts, Sander Dijkhuis, Vincent de Haan +1
Triangulations of the cube into a minimal number of simplices without additional vertices have been studied by several authors over the past decades. For this so-ca…
On the Subspace Projected Approximate Matrix method
Jan H. Brandts, Ricardo Reis da Silva
We provide a comparative study of the Subspace Projected Approximate Matrix method, abbreviated SPAM, which is a fairly recent iterative method to compute a few eigenvalues of a He…
Normalitity preserving perturbations and augmentations and their effect on the eigenvalues
Ricardo Reis da Silva, Jan H. Brandts
We revisit the normality preserving augmentation of normal matrices studied by Ikramov and Elsner in 1998 and complement their results by showing how the eigenvalues of the origina…