This example demonstrates a simple data-loading and transformation workflow using D3. It fetches a CSV file containing the classic Iris dataset and uses `d3.csvParse` to convert the raw text into an array of objects, subsequently coercing the numeric measurement columns to numbers. The resulting parsed data is displayed as formatted JSON inside a `<pre>` element. The visualization uses a minimal state management pattern, with a `setState` callback triggering re-renders, and leverages D3’s `select` and `join` for DOM updates.