Triangular grid-based rapid mapping of scattered data
LI Xiao-Dong1,2,3, JIN Sheng1,2, WANG Yang-Ling1,2, ZHANG Jia-Hong4, CHENG Li-Hui1,2
1. School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China; 2. Geo-detection and instruments Laboratory, Ministry of Education, China University of Geosciences, Beijing 100083, China; 3. Non-ferrous Metals and Nuclear Industry Geological Exploration Bureau of Guizhou, Geophysical and Geochemical Exploring Group, Dujun 558004, China; 4. China Aero Geophysics Survey & Remote Sensing Center foe Land and Resources, Beijing 100083, China
Abstract：Conventional contour mapping performs interpolation based on a rectangular grid. A linear interpolation method is presented in this paper based on triangular mesh. Triangular mesh can better approximate the boundary of scattered data and the morphology of geophysical field, which makes the contour maps smoother. By searching boundary, triangulated mesh, linear interpolation, search contours, Bezier curves and smooth contours, five steps can be carried out quickly for any scattered data mapping. The actual data mapping results show that the interpolation method is good in that no data extrapolation is needed, the contour map obtained directly reflect the spatial location of scattered data, and the mapping is speeded. The method can therefore greatly improve the efficiency of the actual work.
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