Long Valence Arousal
Two physiological signals, arousal and valence, are visualized as a long, horizontal, animated line chart. The visualization plots data from `valenceTotal.csv` and `arousalTotal.csv` over epochs, with a thick, gradient-colored stroke transitioning from blue to red. Buttons allow a user to switch between the two datasets, and a "Move" operation shifts the chart horizontally. The implementation uses D3.js version 3.5.17, including `d3.scale.linear`, `d3.svg.line`, and `d3.csv`, within an SVG canvas.