ABSTRACT
Some sufficient conditions ensuring that the subdirect sum of p-norm strictly diagonally dominant [or, for short, SDD(p)] matrices is in the class of SDD(p) matrices, are given. In particular, it is shown that the subdirect sum of overlapping principal submatrices of an SDD(p) matrix is also an SDD(p) matrix. Some examples are also given that illustrate the conditions presented.
Acknowledgements
The authors thank the editor and anonymous referees for their useful and constructive suggestions, which have greatly helped to improve the presentation of this paper.
Disclosure statement
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