{"version":"1.0","type":"rich","title":"Melting Data for Multiple Lines","description":"This example visualizes population over time by region using multiple smoothed lines, with a color legend and axis labels. It relies on D3 v5 APIs including `nest()`, `scaleTime`, `scaleLinear`, `scaleOrdinal`, `axisBottom`, `axisLeft`, and `line()`, rendering with SVG. Data is melted from wide to long format using a custom function, combining UN population estimates (1950–2014) with medium-variant projections (2015–2100) loaded via `csv`. Lines are drawn with `curveBasis` and sorted by final population value.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/16e2b421b5f94f9b9bd3f56db958b620?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}