开车到香槟

画出从美国 300 个最大的城市到沃尔夫勒姆研究公司在伊利诺伊州香槟市的总部的道路.

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champaign = Entity["City", {"Champaign", "Illinois", "UnitedStates"}]

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us = Entity["Country", "UnitedStates"]

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这是美国最大城市的列表.

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Length[cities = CityData[{Large, "UnitedStates"}]]

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计算到香槟的旅行路径.

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roads = Quiet@TravelDirections[{#, champaign}, "TravelPath"] & /@ cities;

消去几个失败的例子，例如从檀香山到香槟.

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Length[roads = Cases[roads, _GeoPath]]

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绘制地图.

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GeoGraphics[{ GeoStyling[White], Polygon[us], Red, Opacity[.1], roads, Black, Opacity[0.6], Point[cities], Blue, Opacity[1], PointSize[Large], Point[champaign] }, GeoBackground -> LightBlue, ImageSize -> 600, GeoRange -> us] // Rasterize

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