Gist 5967514

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Last edited Jul 10, 2013

Created on Jul 10, 2013

This example displays a map of U.S. counties using a TopoJSON shapefile from the U.S. Census Bureau, rendered as gray-filled paths with white borders that turn red on hover. It shows the geographic boundaries of counties and responds to clicks, though the click behavior only logs to the console. The visualization uses D3 v3’s `d3.geo.path()` to project and draw the SVG paths, and TopoJSON’s `topojson.feature` to extract GeoJSON features from the topology. The map is static, with no zoom or pan, and the hover effect is the only interactive styling.

AI-generated description

A demo of TopoJSON on a U.S. counties shapefile from the U.S. census bureau. The same TopoJSON file can also be used to show states.

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