allsegs: A Comprehensive List of Polygon Segments for Contour Levels

allsegs : [level0segs, level1segs, ...] List of all the polygon segments for all the levels. For contour lines len(allsegs) == len(levels), and for filled contour regions len(allsegs) = len(levels)-1. The lists should look like :: level0segs = [polygon0, polygon1, ...] polygon0 = [[x0, y0], [x1, y1], ...] 中文内容：allsegs是一个包含所有层级的多边形线段的列表。对于等高线，len(allsegs)等于len(levels)，而对于填充等高线区域，len(allsegs)等于len(levels)-1。列表应该如下所示： level0segs = [polygon0, polygon1, ...] polygon0 = [[x0, y0], [x1, y1], ...]