The following example illustrates how you can create a structure array which contains the coordinates of manually selected data points in a 2-D plot.
1. Execute the following at the command prompt:
2. Click the Data Cursor button on the toolbar of the generated figure.
3. Click any point of your choice on the line in the figure.
4. While pressing the Alt key, repeat step 3 as many times as you like until you have selected your desired set of points.
5. Right-click (or control-click if you are on a Mac) anywhere on the figure, and select the 'Export Cursor Data to Workspace...' option from the context menu.
6. Accept the default variable name, "cursor_info", and click "OK".
7. Type "cursor_info.Position" at the MATLAB command prompt and hit "Enter".
The structure array "cursor_info" contains all information regarding selection sequence, x- and y-coordinates of the points selected. Note that for 3-D figures, the selection sequence value is replaced by the z-coordinate value for the points selected.
Also note that the "cursor_info" varable will not appear in the Workspace browser until you complete step 7 above.
It is possible to obtain the data cursor information in the MATLAB workspace programmatically. The following example and the documentation link illustrates how to use the datacursormode function to obtain data cursor information programmatically:
fig = figure;
z = peaks;
dcm_obj = datacursormode(fig);
Now, click on the line to place datatip before executing the next line of code.
c_info = getCursorInfo(dcm_obj)