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arXiv · 1502.01671

Local asymptotic Euler-Maclaurin expansion for Riemann sums over a semi-rational polyhedron

Abstract

Consider the Riemann sum of a smooth compactly supported function h(x) on a polyhedron in R^d, sampled at the points of the lattice Z^d/t. We give an asymptotic expansion when t goes to infinity, writing each coefficient of this expansion as a sum indexed by the faces f of the polyhedron, where the f-term is the integral over f of a differential operator applied to the function h(x). In particular, if a Euclidean scalar product is chosen, we prove that the differential operator for the face f can be chosen (in a unique way) to involve only normal derivatives to f. Our formulas are valid for a semi-rational polyhedron and a real sampling parameter t, if we allow for step-polynomial coefficients, instead of just constant ones.

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BibTeXRIS

Nicole Berline, Michele Vergne. 2015-04-29. Local asymptotic Euler-Maclaurin expansion for Riemann sums over a semi-rational polyhedron. https://arxiv.org/abs/1502.01671

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