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Interpolation of Discretely-Sampled Density Fields

Will Saunders·Bill E. Ballinger
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Abstract

We present a new technique for the interpolation of discretely-sampled non-negat ive scalar fields across regions of missing data. Any set of basis functions can be used, though the method is fastest when they are close to orthogonal. We sho w how the technique may be efficiently applied when the discrete sampling rate v aries across the field. Regularisation is desirable to avoid over-fitting noisy data, and is necessary when the regions of missing data are larger than the requ ired resolution. We present and investigate methods for such regularisation.

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Will Saunders, Bill E. Ballinger. 2000-05-31. Interpolation of Discretely-Sampled Density Fields. https://arxiv.org/abs/astro-ph/0005606

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