California Population Density II

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California Population Density II

✓ Published0🌍 Public

Last edited Nov 13, 2016

Created on Nov 13, 2016

A choropleth map of California displays population density per square mile across 23,198 block groups, using a sequential red color scale and a square-root axis legend. Drawn with `d3.geoPath` and SVG, the visualization loads topology from a preprocessed `topo.json` file, created by scripts that download Census block group boundaries and ACS population data via the Census API. The `prepublish` script projects, joins, and simplifies the data using `geo2topo`, `topomerge`, and `topoquantize`. County borders are overlaid as semi-transparent outlines.

AI-generated description

A variation of my California population density map using California’s 23,198 block groups rather than its 8,043 tracts. The example exhibits how useful the Census API is: the prepublish script here can automatically grabs the list of counties for the desired state and then the population data for each block group.

gpl-3.0 Licensed

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