This example visualizes a bar chart of student grades from a CSV file, with each bar’s width proportional to the numeric value in the Grade column. The code uses d3.csv to load votiOne.csv, then appends SVG rectangles to a 500×500 canvas, positioning them vertically with each row’s index and setting the bar width directly from the parsed data. Written with D3 v4, it renders entirely as SVG elements, showing the raw mapping from tabular data to geometric marks without axes, scales, or additional styling.