{"version":"1.0","type":"rich","title":"Melting Data for Multiple Lines","description":"This example visualizes population over time by region, showing multiple lines that trace changes from 1950 to 2100. It uses D3 v5 with SVG rendering, employing `scaleTime`, `scaleLinear`, and `scaleOrdinal` for scales. The code melts wide-format UN population data into tidy rows using a custom `melt` function, then nests it with `d3.nest()` to generate paths via `d3.line()`. A color legend and gridlines are added, with data sourced from UN population estimates and medium-variant projections.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/83499d7f90464f768498dad8beba3939?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}