Best approximation of functions by log-polynomials
نویسندگان
چکیده
Lasserre [32] proved that for every compact set K⊂Rn and even number d there exists a unique homogeneous polynomial g0 of degree with K⊂G1(g0)={x∈Rn:g0(x)≤1} minimizing |G1(g)| among all such polynomials g fulfilling the condition K⊂G1(g). This result extends notion Löwner ellipsoid, not only from convex bodies to arbitrary sets (which was immediate if d=2 by taking hulls), but also ellipsoids level an degree. In this paper we extend class non-negative log-concave functions in two different ways. One them is straightforward extension known results, other one suitable uniqueness solution corresponding problem characterization terms some ‘contact points’.
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ژورنال
عنوان ژورنال: Journal of Functional Analysis
سال: 2022
ISSN: ['0022-1236', '1096-0783']
DOI: https://doi.org/10.1016/j.jfa.2021.109344