Specifies the functionality of a left-click on the chart. The following modes are available:
Zoom | Zoom in: Users can left-click and drag on the chart to zoom in or out. Dragging to the right creates a hollow rectangle. When the user releases the mouse button, the viewable space in the chart will zoom in to a rectangle. 
Zoom out: Left-click and dragging to the left will not create a rectangle, but releasing the mouse button will zoom back out. |
Pan | Allows users to Pan the chart horizontally or vertically by left-click and dragging. The Pan mode may be used after using the Zoom mode: doing so allows panning within the zoomed in view-space. |
Mark | While in Mark mode, a left click will target the closest point on the nearest pen, and return the value and timestamp of that point. 
|
X-Trace | Similar to Mark, X-Trace will instead show the values of all pens at the selected point in time. 
|