This example visualizes the Iris dataset as a scatter plot of petal length against sepal width, with each flower represented by a circle. It uses React to render SVG elements, while d3-scale’s `scaleLinear` computes the x and y positions and d3-array’s `extent` sets the domains. Custom React components (AxisBottom, AxisLeft, Marks) generate ticks and circles. Data loads asynchronously via d3-fetch’s `csv` from a GitHub gist. The chart includes rotated and positioned axis labels, and hover tooltips using SVG `<title>` elements.