Nonsingularity and -matrices.
Jiří Rohn (1990)
Aplikace matematiky
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New proofs of two previously published theorems relating nonsingularity of interval matrices to -matrices are given.
Jiří Rohn (1990)
Aplikace matematiky
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New proofs of two previously published theorems relating nonsingularity of interval matrices to -matrices are given.
Miroslav Fiedler, Vlastimil Pták (1962)
Czechoslovak Mathematical Journal
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Thomas Ernst (2015)
Special Matrices
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In this second article on q-Pascal matrices, we show how the previous factorizations by the summation matrices and the so-called q-unit matrices extend in a natural way to produce q-analogues of Pascal matrices of two variables by Z. Zhang and M. Liu as follows [...] We also find two different matrix products for [...]
Ljiljana Cvetković, Vladimir Kostić, Maja Nedović (2015)
Open Mathematics
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In this paper we present a nonsingularity result which is a generalization of Nekrasov property by using two different permutations of the index set. The main motivation comes from the following observation: matrices that are Nekrasov matrices up to the same permutations of rows and columns, are nonsingular. But, testing all the permutations of the index set for the given matrix is too expensive. So, in some cases, our new nonsingularity criterion allows us to use the results already...
M. Rajesh Kannan, K.C. Sivakumar (2014)
Discussiones Mathematicae - General Algebra and Applications
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Let A and B be M-matrices satisfying A ≤ B and J = [A,B] be the set of all matrices C such that A ≤ C ≤ B, where the order is component wise. It is rather well known that if A is an M-matrix and B is an invertible M-matrix and A ≤ B, then aA + bB is an invertible M-matrix for all a,b > 0. In this article, we present an elementary proof of a stronger version of this result and study corresponding results for certain other classes as well.
Raphael Loewy (2012)
Open Mathematics
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Let A be an n×n irreducible nonnegative (elementwise) matrix. Borobia and Moro raised the following question: Suppose that every diagonal of A contains a positive entry. Is A similar to a positive matrix? We give an affirmative answer in the case n = 4.