Why is there no DataIndex field in cursor_info for scatter plots?

Export cursor data to the workspace using the following steps: 1. Generate a scatter plot using the following code:   [x, y] = meshgrid (0: 0.1: 1.0: .1: 1); scatter(x(:), y(:),10) 2. Add a few data cursors on the figure. 3. Right-click on the figure and select the ‘Export Cursor Data to Workspace’ option. The "cursor_info" structure appears in the workspace. This structure has sub-structures corresponding to each data cursor on the plot. I see that each of these sub-structures has two fields: ‘Target’ and ‘Position’. However, for a plot generated using the PLOT function (e.g., x1 = [1 2 3]; y1 = [4 5 6]; plot(x1,y1);), I find that the corresponding data cursor structures have three fields: ‘Target’, ‘Position’ and ‘DataIndex’. Note the additional 'DataIndex' field for data cursors in the latter case. Why is there no such 'DataIndex' field in cursor_info for scatter plots?