Choropleth Map with Interactive Filtering
A choropleth map of global economies uses color to encode each country’s economic group, with an interactive color legend that filters the map by clicking a category. Pan and zoom via d3.zoom reveal spatial patterns, while hovering shows country names and values through SVG titles. The visualization is built with d3.geoNaturalEarth1 and d3.geoPath, using ordinal color scaling with d3.scaleOrdinal and d3.schemeSpectral. Data comes from the world-atlas TopoJSON and TSV files, rendered as SVG paths, with the legend updating opacity to dim unselected countries.