Merged Choropleth

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Merged Choropleth

✓ Published0🌍 Public

Last edited Nov 13, 2016

Created on Nov 13, 2016

This choropleth map visualizes population density across California census tracts, using the 2014 American Community Survey 5-Year Estimate. The map merges adjacent tracts with similar density into single polygons, reducing the file size from 1.5M to 328K and improving rendering speed and visual clarity. The d3.geoPath renders the projected shapes, while d3.scaleThreshold and d3.schemeOrRd assign colors, and d3.scaleSqrt positions the legend. The code uses topomerge and toposimplify from the topojson library to consolidate boundaries, with county borders overlaid as an outline.

AI-generated description

Source: American Community Survey, 2014 5-Year Estimate

A variation of my California population density map using topomerge to combine census tracts in the same density interval. The resulting TopoJSON file is substantially smaller (328K instead of 1.5M), renders faster, and looks better due to fewer antialiasing artifacts!

gpl-3.0 Licensed

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