{"version":"1.0","type":"rich","title":"bar chart with legend","description":"A bar chart displays four fixed values—20, 30, 40, and 10—as vertical bars rendered in SVG. The chart is built using D3 v4 within a custom `BarChart` class, which configures margins and appends a `<g>` element to the body. The code defines a render method but leaves it empty, so the bars themselves are not actually drawn; only the SVG container is initialized. The example demonstrates a minimal class-based structure for a D3 bar chart, with the data array hardcoded in the script.","provider_name":"VizHub AI Studio","provider_url":"https://next.vizhub.com","html":"<iframe src=\"https://next.vizhub.com/viz/gist-b7950eb635294a70126908a9954d8d61?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"1\"></iframe>","width":960,"height":500,"cache_age":3600}