6 citations · 7 across the 9 of their papers we have counts for
4 papers · 1 filter
Commutation matrices and Commutation tensors
Changqing Xu
The commutation matrix was first introduced in statistics as a transposition matrix by Murnaghan in 1938. In this paper, we first investigate the commutation matrix which is employ…
On {0,1} CP Tensors and CP Multi-hypergraphs
Changqing Xu, Zhibing Chen, Liqun Qi
A doubly nonnegative matrix can be written as a Gramian matrix, and a completely positive matrix can therefore be written as a Gramian matrix of some nonnegative vectors. In this p…
Completely Positive Tensors and Multi-Hypergraphs
Changqing Xu, Ziyan Luo, Liqun Qi
Completely positive graphs have been employed to associate with completely positive matrices for characterizing the intrinsic zero patterns. As tensors have been widely recognized…
When does cp-rank equal rank?
Wasin So, Changqing Xu
The problem of finding completely positive matrices with equal cp-rank and rank is considered. We give some easy-to-check sufficient conditions on the entries of a doubly nonnegati…