2023/04/28 by Geng, Jiaxin, Wang, Heping
#41A63 #65C05 #65D15 #65Y20 #FOS: Mathematics #Numerical Analysis (math.NA)
paper · doi:10.48550/arxiv.2304.14748
We study multivariate approximation of periodic function in the worst case setting with the error measured in the L_∞ norm. We consider algorithms that use standard information Λ\rm std consisting of function values or general linear information Λ\rm all consisting of arbitrary continuous linear functionals. We investigate the equivalences of various notions of algebraic and exponential tractability for Λ\rm std and Λ\rm all under the absolute or normalized error criterion, and show that the power of Λ\rm std is the same as the one of Λ\rm all for some notions of algebraic and exponential tractability. Our result can be applied to weighted Korobov spaces and Korobov spaces with exponential weight. This gives a special solution to Open problem 145 as posed by Novak and Woźniakowski (2012).