MD Counties Map_Step 1

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MD Counties Map_Step 1

✓ Published0🌍 Public

Last edited May 2, 2017

Created on May 2, 2017

This choropleth map displays population density for census tracts in Montgomery County, Maryland, using a threshold color scale from light to dark red. It renders SVG paths via `d3.geoPath` with a conic conformal projection, merging TopoJSON tract boundaries from a local dataset. The code loads tract geometries and population data with `d3.queue`, calculates density by dividing population by land area, and applies `d3.scaleThreshold` with `d3.schemeOrRd`. A legend built with `d3.axisBottom` and a power scale explains the color ranges.

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