Results 21 to 30 of about 55,699 (240)
Compressive Optical Spectrometry Based on Sequency-Ordered Hadamard Transform
IEEE Photonics Journal, 2020 We propose a compressive Hadamard transform spectrometer (CHTS) based on the energy compaction trait of the sequency-ordered Hadamard matrix (SOHM), in which the spectrum is reconstructed from compressed measurements using simple matrix multiplication ...
Yi Zhang +3 more
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Robust Hadamard matrices, unistochastic rays in Birkhoff polytope and equi-entangled bases in composite spaces [PDF]
, 2018 We study a special class of (real or complex) robust Hadamard matrices, distinguished by the property that their projection onto a $2$-dimensional subspace forms a Hadamard matrix.
Gąsiorowski, Adam +2 more
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A SKEW HADAMARD MATRIX OF ORDER 36 [PDF]
Journal of the Australian Mathematical Society, 1970 Hadamard matrices exist for infinitely many orders 4m, m ≧ 1, m integer, including all 4m < 100, cf. [3], [2]. They are conjectured to exist for all such orders. Skew Hadamard matrices have been constructed for all orders 4m < 100 except for 36, 52, 76, 92, cf. the table in [4]. Recently Szekeres [6] found skew Hadamard matrices of the order 2(pt
Goethals, J.M., Seidel, J.J.
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Embedding and Extension Properties of Hadamard Matrices Revisited
Special Matrices, 2018 Hadamard matrices have many applications in several mathematical areas due to their special form and the numerous properties that characterize them. Based on a recently developed relation between minors of Hadamard matrices and using tools from calculus ...
Christou Dimitrios +2 more
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Partitioned and Hadamard product matrix inequalities [PDF]
Journal of Research of the National Bureau of Standards, 1978 This note is partly expositor). Inequalities relating inversion with, respectively, extraction of principal submatriees and the Hadamard product in the two possible orders are developed in a simple and unified way for positive definite matrices. These inequalities are known, hut we also characterize the cases of equality and strict inequality.
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Sylvester Hadamard matrices revisited
Special Matrices, 2014 In this work we revisited some properties of Sylvester Hadamard matrices of order 2k. Based onlyon the existence of a base from which any Sylvester Hadamard matrix can be constructed, we prove that theirrows (columns) are closed under addition and that ...
Mitrouli M.
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Matrix Completions, Norms, and Hadamard Products [PDF]
Proceedings of the American Mathematical Society, 1993 The author obtains a necessary and sufficient condition for \(X_ 0\in S\subset H_ n\) to attain the maximum in the problem \(\max\{\lambda_{\min}(A+X):X\in S\}\), where \(A\in H_ n\) is a fixed matrix, \(H_ n\) is the space of \(n\times n\) Hermitian matrices, and \(S\) is a closed convex set.
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A Hadamard product involving inverse-positive matrices
Special Matrices, 2015 In this paperwe study the Hadamard product of inverse-positive matrices.We observe that this class of matrices is not closed under the Hadamard product, but we show that for a particular sign pattern of the inverse-positive matrices A and B, the Hadamard
Gassó Maria T. +2 more
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On Some Estimate for the Norm of an Interpolation Projector
Моделирование и анализ информационных систем, 2022 Let $Q_n=[0,1]^n$ be the unit cube in ${\mathbb R}^n$ and let $C(Q_n)$ be a space of continuous functions $f:Q_n\to{\mathbb R}$ with the norm $\|f\|_{C(Q_n)}:=\max_{x\in Q_n}|f(x)|.$ By $\Pi_1\left({\mathbb R}^n\right)$ denote a set of polynomials in $n$
Mikhail V. Nevskii
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Constructions of complex Hadamard matrices via tiling Abelian groups [PDF]
, 2006 Applications in quantum information theory and quantum tomography have raised current interest in complex Hadamard matrices. In this note we investigate the connection between tiling Abelian groups and constructions of complex Hadamard matrices.
Ferenc Szöllősi +4 more
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