Design And Application Of Visualization System For Geographical Quantitative Graphic Thematic Symbol

In the era of big data,the presentation ability of traditional statistical thematic maps is increasingly difficult to meet the needs of popular cartography.The simple structure and single form of statistical symbols make it difficult to fully display the development trend contained in statistical data.Geoscience quantitative graphs are diverse in form,flexible in combination and intuitive in comparison,and can represent large amount of information,multiple indicators and geographic data of different units of measurement.This paper selects several novel quantitative graph coordinate systems to design and implement some related symbols,and introduces them into thematic maps.It has positive significance for the expression of the laws of geoscience quantitative data,the diversification of display forms and the convenience of map making process.On the basis of analyzing the research status at home and abroad,this paper establishes the correspondence between different feature statistics and quantitative graphs from the perspective of quantitative graphic thematic symbol application,studies the generation algorithm of quantitative graphics thematic symbols,and realizes the design and application of the visualization system of quantitative graphics thematic symbols on the platform of ArcGIS Engine.The system optimizes data processing,cartographic flow and symbol selection module,which reduces the complexity of cartographic work,and provides a large number of new symbols with rich styles that can fully show the law of data.The main contents of this paper are as follows:(1)A number of quantitative graph coordinate systems with novel styles are selected,the symbolic system of quantitative graphs is subdivided based on the internal structure and shape characteristics of basic graphs and combined graphs,and the advantages of different quantitative graphs in the presentation of statistical data are extracted from the graphical style.(2)According to the number of indicators and the logical relationship between indicators,the statistical data were reasonably classified.The corresponding relationship between different characteristic data and different types of quantitative graphics is established,which provides a theoretical basis and reference for the application of geographical quantitative graphics and a more suitable way for the expression of related characteristic data.(3)According to the representation principle of quantitative graphics,the drawing algorithms of different quantized graph symbols are designed.In order to facilitate the user to change the symbol shape,the symbol control model to adjust parameters is created,the quantitative graphics thematic symbol shape control model building is completed,and the positioning algorithm based on polygon area segmentation idea is proposed to adaptively display the graphic symbol.(4)From the perspective of thematic mapping,the feasibility of the visualization system is analyzed.Based on the ArcGIS Engine platform,the quantitative graphic symbol class is designed,the statistical symbol types are extended,and the statistical principle of “statistical graphics adapting to data features” is used to optimize the production process of the statistic thematic map,which realizes the use of quantitative graphics in map drawing.