d3 + TopoJSON

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✓ Published0🌍 Public

Last edited Mar 25, 2018

Created on Mar 25, 2018

This example shows a map of U.S. counties rendered as gray SVG paths with white borders, which turn red on hover. It loads a TopoJSON file from a gist and converts it to GeoJSON using `topojson.feature`, then projects and draws each county with `d3.geo.path()`. The code relies on d3.v3 and TopoJSON v1, and the map uses a default projection without custom zoom or interaction.

AI-generated description

Working with TopoJSON and d3.js projections for mapping geospatial data.

forked from <a href='http://bl.ocks.org/mbostock/'>mbostock</a>'s block: <a href='http://bl.ocks.org/mbostock/4122298'>U.S. Counties TopoJSON</a>

forked from <a href='http://bl.ocks.org/almccon/'>almccon</a>'s block: <a href='http://bl.ocks.org/almccon/410b4eb5cad61402c354afba67a878b8'>d3 + TopoJSON</a>

gpl-3.0 Licensed

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