This example visualizes the Iris dataset as an interactive scatterplot, mapping petal length to the x-axis, sepal length to the y-axis, and petal width to circle radius, with species indicated by color (blue, red, or black). It uses D3 v7’s `csv`, `scaleLinear`, `scaleSqrt`, `extent`, and `max` to load and scale the data, then renders SVG circles via a data join. Axis are drawn with `axisLeft` and `axisBottom`. The plot fills the browser window, and hovering reveals species and measurement details via tooltips.