Line Chart with Multiple Lines
This line chart displays one week of temperature data in degrees Celsius for cities worldwide, sourced from Data Canvas - Sense Your City. The visualization plots temperature over time, with each city represented by a colored line and a legend identifying the cities. It uses d3.csv to load data, d3.scaleTime and d3.scaleLinear for axes, d3.nest to group by city, and d3.line with curveBasis for smooth paths. The SVG rendering includes gridlines, axis labels, and a custom color legend built with d3.scaleOrdinal and schemeCategory10.