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Apply four color theorem to the map of Florida?


I'm attempting to apply the Four Color Theorem to a map of Florida and I'm following an example available among the standard collection of examples located at: ref/GeoGraphics; "Neat Examples" (provided by my Mathematica software). Unfortunately; the following:

EntityProperty["AdministrativeDivision", "BorderingCounties"] 

doesn't work when I evaluate it using my Mathematica software. I found an alternative way to get around this difficulty and I can apply the four color theorem to subareas of the map of Florida but, the same code that I use for the subareas will not work for the whole state. I have built the attached Mathematica notebook explaining my problem in detail. Thank you for your help!

27 days ago

I am going to assume that in your solution you want a nested list of string values that represent the Counties with which you are interested. In that case, you will need to apply the EntityValue function to a valid Entity Data Types. However, you will first need to obtain an Entity Class from your strings that represent the Entity Types you seek.

xx = EntityValue[
   EntityClass["AdministrativeDivision", "USCountiesFlorida"], 

EntityValue[#, "Name"] & /@ xx
POSTED BY: Joel Gilly
10 days ago

@Joel Gilly Thank you for responding to my query. I have no trouble getting the list of counties as you described. The trouble occurs when attempting to color the counties as described in another Mathematica notebook located at: Thank you for your help!

9 days ago

Did you already try this?

Find a Four-Coloring of a Map of Europe

POSTED BY: Aeyoss Antelope
7 days ago

@Aeyoss Antelope: Yes Aeyoss; that is indeed the example that I'm emulating; with counties in Florida instead of countries in Europe. Thank you.

6 days ago

Group Abstract Group Abstract