Nilpotent completions of partial upper triangular matrices
نویسندگان
چکیده
منابع مشابه
completions on partial matrices ?
An n × n matrix is called an N0-matrix if all its principal minors are nonpositive. In this paper, we are interested in N0-matrix completion problems, that is, when a partial N0-matrix has an N0-matrix completion. In general, a combinatorially or non-combinatorially symmetric partial N0-matrix does not have an N0-matrix completion. Here, we prove that a combinatorially symmetric partial N0-matr...
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Nonnegative nilpotent lower triangular completions of a nonnegative nilpotent matrix are studied. It is shown that for every natural number between the index of the matrix and its order, there exists a completion that has this number as its index. A similar result is obtained for the rank. However, unlike the case of complex completions of complex matrices, it is proved that for every nonincrea...
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ژورنال
عنوان ژورنال: Linear Algebra and its Applications
سال: 2004
ISSN: 0024-3795
DOI: 10.1016/j.laa.2004.04.018