This example shows a single circle centered within an SVG canvas that measures 960 by 500 pixels, with its radius set to half the canvas height. The visualization demonstrates basic SVG shape creation using D3 v5’s selection and append methods, where the circle’s position and size are derived from the SVG’s width and height attributes. The code uses `select` from D3 to access the SVG element and `attr` to set the circle’s radius (`r`) and center coordinates (`cx`, `cy`), with the data source being the hardcoded SVG dimensions rather than an external dataset.