Non-equidistant approximate DFT based on Z-splines
نویسنده
چکیده
In this paper, we consider an algorithm that efficiently evaluates a trigonometric polynomial at arbitrarily spaced nodes. It is based on the approximation of the polynomial by a function we can evaluate easily. We are particularly interested in the case where we interpolate the trigonometric polynomial using high-order cardinal interpolation kernels known as Z-splines, which we construct and study in a general setting. Introduction We are interested in the fast evaluation of a trigonometric polynomial f(xj) = ∑
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تاریخ انتشار 2006