The α-scalar diagonal stability of block matrices

We generalize two results: Kraaijevanger's 1991 characterization of diagonal stability via Hadamard products and the block matrix version of the closure of the positive definite matrices under Hadamard multiplication. We restate our generalizations in terms of P-alpha-rnatrices and alpha-scalar diagonally stable matrices. (c) 2005 Elsevier Inc. All rights reserved.