{"version":"1.0","type":"rich","title":"Melting Data for Multiple Lines","description":"This example visualizes population over time by region, displaying multiple trend lines across a Cartesian coordinate system. The chart uses D3’s `nest` and `line` with `curveBasis` to structure and smooth the data, while `scaleTime`, `scaleLinear`, and `scaleOrdinal` manage the axes and color encoding. A color legend, generated by a custom `colorLegend` function, identifies each region. The data comes from UN population estimates and medium-variant projections, processed through a custom `melt` function that reshapes the dataset.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/914f39d8085e4392bebd2cbd521c1dc8?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}