Results 11 to 20 of about 522,371 (218)
An algorithm for approximation of functions
Journal of Mathematical Analysis and Applications, 1973 AbstractThis paper considers a problem of approximation of functions proposed by Bellman [1]. The results include a representation lemma for the solutions and an algorithm for computing such solutions. A sufficient condition for the convergence of the algorithm to the optimal solutions is shown to be related to the uniqueness of solutions of a pair of ...
R. Chattopadhyay
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Algorithms for the Rational Approximation of Matrix-Valued Functions [PDF]
SIAM Journal on Scientific Computing, 2021 A selection of algorithms for the rational approximation of matrix-valued functions are discussed, including variants of the interpolatory AAA method, the RKFIT method based on approximate least squares fitting, vector fitting, and a method based on low-rank approximation of a block Loewner matrix. A new method, called the block-AAA algorithm, based on
Ion Victor Gosea, Stefan Güttel
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An Algorithm for Best Generalised Rational Approximation of Continuous Functions [PDF]
Set-Valued and Variational Analysis, 2022 The motivation of this paper is the development of an optimisation method for solving optimisation problems appearing in Chebyshev rational and generalised rational approximation problems, where the approximations are constructed as ratios of linear forms (linear combinations of basis functions).
R. Díaz Millán +2 more
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Physico-mathematical modelling and informational technologies, 2021 Effective by precision algorithms for approximation of functions from the Gelder class by Fourier’s series, using the Fourier’s coefficients, calculated with high precision, are constructed, and the evaluations of their basic characteristics (precision ...
Olena Kolomys
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Symmetry-conserving maximally projected Wannier functions [PDF]
Physical review B, 2021 To obtain a local description from highly accurate density functional theory codes that are based on modified plane wave bases, a transformation to a local orthonormal Wannier function basis is required.
K. Koepernik +11 more
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The AAAtrig Algorithm for Rational Approximation of Periodic Functions [PDF]
SIAM Journal on Scientific Computing, 2021 We present an extension of the AAA (adaptive Antoulas--Anderson) algorithm for periodic functions, called 'AAAtrig'. The algorithm uses the key steps of AAA approximation by (i) representing the approximant in (trigonometric) barycentric form and (ii) selecting the support points greedily.
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NeuReach: Learning Reachability Functions from Simulations
International Conference on Tools and Algorithms for Construction and Analysis of Systems, 2022 . We present NeuReach , a tool that uses neural networks for predicting reachable sets from executions of a dynamical system. Unlike existing reachability tools, NeuReach computes a reachability function that outputs an accurate over-approximation of the
Dawei Sun, S. Mitra
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A Formal Perspective on Byte-Pair Encoding [PDF]
Annual Meeting of the Association for Computational Linguistics, 2023 Byte-Pair Encoding (BPE) is a popular algorithm used for tokenizing data in NLP, despite being devised initially as a compression method. BPE appears to be a greedy algorithm at face value, but the underlying optimization problem that BPE seeks to solve ...
Vilém Zouhar +6 more
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Mathematical models and soil fertility management software [PDF]
E3S Web of Conferences, 2020 The article presents the results of studies on parametric approximation in spaces R2 (functions of one variable), R3 (functions of two variables) and Rn(n>3) (functions of three or more variables).
Mitrofanov Sergey +3 more
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Under-Approximating Expected Total Rewards in POMDPs [PDF]
International Conference on Tools and Algorithms for Construction and Analysis of Systems, 2022 We consider the problem: is the optimal expected total reward to reach a goal state in a partially observable Markov decision process (POMDP) below a given threshold? We tackle this -- generally undecidable -- problem by computing under-approximations on
Alexander Bork, J. Katoen, Tim Quatmann
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