Results 261 to 270 of about 5,113,236 (295)

Positive Definite Functions and States

The Annals of Mathematics, 1954
This paper is concerned with the relation between the set P of continuous, positive definite functions on a locally compact group G and the set F of continuous, positive linear functionals on the group operator algebra A of G. This concern is motivated by an attempt to establish a connection between the procedure of Gelfand and Raikov [3] with the ...
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STRICT POSITIVE DEFINITENESS ON SPHERES

Analysis, 1999
Strictly positive definite functions on the unit sphere \(S^m\) in \(\mathbb{R}^{m+1}\) provide a tool for interpolating scattered data on \(S^m\). If there are \(n\) distinct points then strictly positive definite functions of order \(n\) are of main interest. Positive definite functions \(f\) on \(S^m\) are characterized by Schoenberg as those having
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View Definition and Positioning in DOOD Systems

Journal of Systems Integration, 1997
Because there is no difference between derivation rules and view definitions, DOOD systems are the best candidates to support an object-oriented view mechanism. Yet, to combine expressive power (i.e. no restriction on queries defining views), reusability and modeling accuracy (i.e. insertion of views into the generalization hierarchy), and consistency (
Ye, X., Parent, Christine, Spaccapietra, Stefano   +2 more
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On Quotients of Positive Definite Functions

Acta Mathematica Hungarica, 2000
Let \(E'\) be the space of distributions with compact support and \(S\) be the space of complex valued Schwartz functions. The main result is: Let \(f:\mathbb R\to \mathbb R\) be the Fourier transform of a real \(T\in E'\). Then \(f\) is the quotient of two positive definite functions from \(S\) if and only if \(f(0)\neq 0\).
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Inequalities for Positive Definite Functions

Mathematical Notes, 2020
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Subdivision Schemes for Positive Definite Matrices

Foundations of Computational Mathematics, 2012
The authors consider subdivision methods generalised from scalar cases to the subdivision of matrices. To this end, they begin with a summary of the basic approaches to subdivision (in the scalar case) by ways of arithmetic and geometric means for instance.
Uri Itai, Nir Sharon
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Unbounded Positive Definite Functions

Canadian Journal of Mathematics, 1969
Let G be an abelian group, written additively. A complexvalued function ƒ, defined on G, is said to be positive definite if the inequality1holds for every choice of complex numbers C1, …, cn and S1, …, sn in G. It follows directly from (1) that every positive definite function is bounded. Weil (9, p.
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On positive definite quadratic forms

form, 2000
Let \(Q\) be a real indefinite quadratic form in 3 or more variables whose coefficients are not all in rational ratio. It was proved by Margulis (1987) that \(Q\) assumes arbitrarily small values at integral points. In this paper a natural analogue of Margulis result has been investigated.
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On Positive Definite Sequences

The Annals of Mathematics, 1946
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On Positive-Definite Functions

Proceedings of the London Mathematical Society, 1956
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