math - 在 Mathematica 中生成拓扑空间图

Question

我有 mathematica 代码来检查集合的集合是否满足拓扑的定义，我现在想以编程方式生成如下图:


如何才能做到这一点？

Answer 1

我不熟悉你的问题，但要从图元创建图，看起来有点像你粘贴的图，你可以这样做:

从“基本”案例开始——

base = {Circle[{-0.4, 0.4}, 0.1], Disk[{0, .125}, 0.05], 
   Text[Style["1", 24], {0, -0.1}],
   Disk[{0.5, .125}, 0.05], Text[Style["2", 24], {0.5, -0.1}], 
   Disk[{1., .125}, 0.05], Text[Style["3", 24], {1., -0.1}], 
   Circle[{.5, 0}, {.9, .5}]};

Graphics[{base}, ImageSize -> 220]

从这里开始向基本案例添加省略号:

Graphics[{base, Circle[{0, 0}, {.15, .3}]}, ImageSize -> 220]

Graphics[{base, Circle[{0, 0}, {.15, .3}], 
  Circle[{0.5, 0}, {.15, .3}], Circle[{0.25, 0}, {.58, .38}]}, 
 ImageSize -> 220]

Graphics[{base, Circle[{0.5, 0}, {.15, .3}], 
  Circle[{0.25, 0}, {.58, .38}], Circle[{0.75, 0}, {.58, .38}]}, 
 ImageSize -> 220]

Graphics[{base, Circle[{0.5, 0}, {.15, .3}], 
  Circle[{1, 0}, {.15, .3}], Red, AbsoluteThickness[6], 
  Line[{{-0.4, -0.5}, {1.4, 0.55}}], 
  Line[{{-0.4, 0.55}, {1.4, -0.5}}]}, ImageSize -> 220]

Graphics[{base, Circle[{0.25, 0}, {.58, .38}], 
  Circle[{0.75, 0}, {.58, .38}], Red, AbsoluteThickness[6], 
  Line[{{-0.4, -0.5}, {1.4, 0.55}}], 
  Line[{{-0.4, 0.55}, {1.4, -0.5}}]}, ImageSize -> 220]

请注意，我在调整这些时设置了 Frame->True 以便我可以看到坐标。