This example displays the classic Iris dataset as a scatter plot, mapping petal length on the x-axis and sepal length on the y-axis. It uses a reusable D3 module pattern with `scaleLinear`, `extent`, `axisLeft`, and `axisBottom` to render SVG circles and axes. The code loads data via `d3.csv` from a gist, parses numeric fields, and applies a configurable margin and radius through a closure-based API. The visualization fills the browser window and uses a full-screen SVG without additional interaction.