Dot density map

d3 Choropleth Map

This example displays Massachusetts town boundaries as a choropleth map using two different projections: a U.S.-oriented Albers projection and a Massachusetts-specific conic conformal projection. The code loads TopoJSON geographic data and renders map outlines with `d3.geoPath` and `d3.geoConicConformal`. A color legend module (`colorLegend`) adds a visual key with circles and text, while hover interactions highlight regions via CSS. The visualization uses SVG rendering with D3 v5 and TopoJSON utilities.

NNilla

75% match

Mass Map 3

A choropleth of Massachusetts is rendered as an enlarged SVG map using a custom d3.geoAlbers projection with adjusted center, rotation, and parallels for regional focus. The code loads TopoJSON from a GitHub gist, converts it to GeoJSON via topojson.feature, and draws each polygon with d3.geoPath. Individual county paths appear in white with teal strokes, emphasizing the state’s borders. The React app fetches and displays the map within a fixed 960×500 viewport, providing a clean, minimalist view of the geography.

74% match

Massachussets

This example visualizes Massachusetts school districts as a choropleth map, with each town randomly assigned one of three colors from a categorical scale. The geographic boundaries are rendered using a conic conformal projection through `d3.geoPath`, while React manages the component structure. Data is loaded from a local TopoJSON file containing town boundaries, and the color mapping is applied via `d3.scaleLinear`. The map is displayed as SVG paths with black strokes highlighting district borders.

11993-INDALKAR

74% match

Mass Map 2

This example renders a choropleth map of Massachusetts using the Albers equal-area conic projection. It displays the state’s geographic boundaries as SVG paths, colored with a teal stroke and fill. The visualization uses React to manage state and rendering, calling `d3.geoPath` with `d3.geoAlbers` to project the GeoJSON data fetched from a GitHub gist via `d3.json`. The `topojson` library’s `feature` function converts the TopoJSON structure into GeoJSON features for plotting.

Dot Density India

A dot density map of India renders each state as a colored polygon on a canvas, using a color-coding scheme where each state's RGB value encodes its index. The visualization projects geographic coordinates through a Mercator projection with d3.geoMercator, and draws the state boundaries using d3.geoPath and topojson. The rendering occurs entirely on a Canvas 2D context, with each polygon filled via a custom drawPolygon function that iterates through coordinate rings. The data comes from a remote TopoJSON file containing Indian state boundaries, loaded asynchronously with d3.json.

AAnimesh Nautiyal

Mass Map 3 add points

This visualization shows a map of Massachusetts with individual crime locations overlaid as small circular points. The map uses the `geoAlbers` projection and `geoPath` to render state boundaries from TopoJSON data. Crime data is loaded from a CSV using `d3.csv`, with each record plotted via `projection([d.lon, d.lat])` into SVG circle elements. The React component structure manages loading states and renders the map with `d3`-powered geographic utilities, displaying points with a distinct fill color against the state's geometry.

Mass Map 3 add points

Mass Crime Map with circle size corresponding to crime/population ratio

This example displays a choropleth-style map of Massachusetts where each circle’s radius encodes the crime-to-population ratio, allowing quick comparison of crime rates across counties. The map uses a `geoAlbers` projection with `geoPath` to render the state boundary, while circles are positioned via `projection` and sized with `scaleSqrt`. Data comes from a CSV file and a TopoJSON file, loaded using `d3.csv` and `d3.json`. The visualization is built with React and D3 v5, rendering in SVG.