Near minimally normed spline quasi-interpolants on uniform partitions
نویسندگان
چکیده
Spline quasi-interpolants are local approximating operators for functions or discrete data. We consider the construction of discrete and integral spline quasi-interpolants on uniform partitions of the real line having small infinite norms. We call them near minimally normed quasi-interpolants: they are exact on polynomial spaces and minimize a simple upper bound of their infinite norms. We give precise results for cubic and quintic quasi-interpolants. Also the quasi-interpolation error is considered, as well as the advantage that these quasi-interpolants present when approximating functions with isolated discontinuities.
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