Results 31 to 40 of about 41,274 (203)
Characterizing graphs with fully positive semidefinite Q-matrices
Linear Algebra and its Applications, 2023 6 ...
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Hyperbolic Relaxation of $k$-Locally Positive Semidefinite Matrices
SIAM Journal on Optimization, 2022 A successful computational approach for solving large-scale positive semidefinite (PSD) programs is to enforce PSD-ness on only a collection of submatrices. For our study, we let $\mathcal{S}^{n,k}$ be the convex cone of $n\times n$ symmetric matrices where all $k\times k$ principal submatrices are PSD.
Grigoriy Blekherman +3 more
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Using distance on the Riemannian manifold to compare representations in brain and in models
NeuroImage, 2021 Representational similarity analysis (RSA) summarizes activity patterns for a set of experimental conditions into a matrix composed of pairwise comparisons between activity patterns.
Mahdiyar Shahbazi +3 more
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A Parallel Approximation Algorithm for Positive Semidefinite Programming
, 2011 Positive semidefinite programs are an important subclass of semidefinite programs in which all matrices involved in the specification of the problem are positive semidefinite and all scalars involved are non-negative.
Jain, Rahul, Yao, Penghui
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LP-based Tractable Subcones of the Semidefinite Plus Nonnegative Cone [PDF]
, 2017 The authors in a previous paper devised certain subcones of the semidefinite plus nonnegative cone and showed that satisfaction of the requirements for membership of those subcones can be detected by solving linear optimization problems (LPs) with $O(n)$
Tanaka, Akihiro, Yoshise, Akiko
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Trace-Inequalities and Matrix-Convex Functions
Fixed Point Theory and Applications, 2010 A real-valued continuous function f(t) on an interval (α,β) gives rise to a map X↦f(X) via functional calculus from the convex set of n×n Hermitian matrices all of whose eigenvalues belong to the interval. Since the subpace of
Tsuyoshi Ando
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Fractional Hadamard powers of positive semidefinite matrices
Linear Algebra and its Applications, 2003 The authors consider the class \(\varphi_n\) of all real positive semidefinite \(n\times n\) matrices, and the subclass \(\varphi^+_n\) of all \(A\in\varphi_n\) with non-negative entries. For a positive, non-integer number \(\alpha\) and some \(A\in \varphi_n^+\), when will the fractional Hadamard power \(A^{\diamondsuit \alpha}\) again belong to ...
Fischer, P., Stegeman, J.D.
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A Unifying Approach to Self‐Organizing Systems Interacting via Conservation Laws
Advanced Intelligent Discovery, EarlyView.The article develops a unified way to model and analyze self‐organizing systems whose interactions are constrained by conservation laws. It represents physical/biological/engineered networks as graphs and builds projection operators (from incidence/cycle structure) that enforce those constraints and decompose network variables into constrained versus ...
F. Barrows +7 more
wiley +1 more source
Logarithmic barriers for sparse matrix cones
, 2012 Algorithms are presented for evaluating gradients and Hessians of logarithmic barrier functions for two types of convex cones: the cone of positive semidefinite matrices with a given sparsity pattern, and its dual cone, the cone of sparse matrices with ...
Andersen, Martin S. +2 more
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The positive semidefiniteness of partitioned matrices
Linear Algebra and its Applications, 1988 The author gives the character of the Löwner order, i.e. for symmetric matrices A and C such that \(C\leq A\), a symmetric matrix B satisfies \(C\leq B\leq A\) if and only if \(tr(R'B)\leq 1/2tr\{R'(A+C)\}+1/4tr(Q_ R)\) for all possible R, where \(Q_ R=\{(A-C)^{1/2}(R+R')(A-C)(R+R')(A- C)^{1/2}\}^{1/2}.\) An application to varieties of problems ...
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