关键词: 信息可视化, 层次结构, 嵌套圆, 评价指标

Abstract: The existed Circle Packing methods mainly take the style of top-down to arrange all the nodes. When the nodes of different layer was arranged, the scaling and translation would cause relative high time complexity of the algorithm, and the size proportional discordance of nodes of different father nodes but the same layer, and it also causes the problems like defective tightness between the layouts of father nodes and child nodes. To solve problems above, on the basis of summarizing methods of arranging brother nodes of the same layer, the algorithm——CRCA(Circle and Rectangle Center Algorithm) was proposed, which took the style of down-top. And an indicator evaluating the layout tightness between father nodes and child nodes was presented, which was called AR(Area Ratio). The Circle Packing method based on CRCA would be applied to the visual analysis on the data of Maximum Residue Limits (MRLs) of pesticides in China (GB2763-2014). After visualizing the MRLs data, it is proved efficient to help users to compare the data and also significant to get a better knowledge of the MRLs data.

Key words: information visualization, hierarchical structure, circle packing, evaluation indicator