Journal of Approximation Theory ( IF 0.9 ) Pub Date : 2021-07-18 , DOI: 10.1016/j.jat.2021.105631 Yurii Kolomoitsev 1 , Jürgen Prestin 1
We study approximation properties of general multivariate periodic quasi-interpolation operators, which are generated by distributions/functions and trigonometric polynomials . The class of such operators includes classical interpolation polynomials ( is the Dirac delta function), Kantorovich-type operators ( is a characteristic function), scaling expansions associated with wavelet constructions, and others. Under different compatibility conditions on and , we obtain upper and lower bound estimates for the -error of approximation by quasi-interpolation operators in terms of the best and best one-sided approximation, classical and fractional moduli of smoothness, -functionals, and other terms.
中文翻译:
周期多元拟插值算子的逼近性质
我们研究了由分布/函数生成的一般多元周期性准插值算子的近似性质 和三角多项式 . 此类运算符包括经典插值多项式 ( 是狄拉克 delta 函数),Kantorovich 型运算符(是一个特征函数)、与小波构造相关的缩放扩展等。在不同的兼容条件下 和 ,我们获得了上限和下限估计 - 准插值算子在最佳和最佳单边近似、经典和分数平滑模量方面的近似误差, -泛函和其他术语。