Abstract
Topographic data sets are often composed of terrain samples arranged in irregular meshes. Many gradient estimation methods require the data to be arranged in a regular mesh; irregular meshes present a difficulty for them. This paper presents a novel method of estimating surface gradients from irregularly spaced inputs. The method is derived using directional derivatives and is shown to be a generalization of traditional finite difference methods. Analytical tests were used to evaluate the method, which was shown to be accurate and robust.
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Meyer, T.H., Eriksson, M. & Maggio, R.C. Gradient Estimation from Irregularly Spaced Data Sets. Mathematical Geology 33, 693–717 (2001). https://doi.org/10.1023/A:1011026732182
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DOI: https://doi.org/10.1023/A:1011026732182