Basic filled contours in D3

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Basic filled contours in D3

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Last edited Nov 7, 2011

Created on Nov 6, 2011

This example displays a two-dimensional scalar field as a filled contour map, with nested color bands representing different value ranges. The visualization uses a custom contouring algorithm based on triangular meshes, which generates both filled polygons for areas and unconnected line segments for contour boundaries. Implemented with D3.js, the code uses linear scales to map data coordinates to screen positions and SVG polygons and paths for rendering. The underlying dataset is a hardcoded 20x20 matrix of numeric values, with a white-to-red color scale encoding the range from -5 to 3.

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