In this post we explain how to add, present and use a graph cursor.

The goal of adding a graph cursor is to find the exact values of a point along the plotted graph, the next example contains a graph of a simple parabolic curve, clicking anywhere on the graph will snap to the nearest point on the graph and show the values on the designated numeric controls.

The goal of adding a graph cursor is to find the exact values of a point along the plotted graph, the next example contains a graph of a simple parabolic curve, clicking anywhere on the graph will snap to the nearest point on the graph and show the values on the designated numeric controls.

To add a graph cursor you need to do the following 2 steps :

**1. Adding the Graph Cursor**

- At the .uir tab of the workspace edit the graph control and click the Cursors button.
- Change the number of cursors to 1 and the mode to "Snap to Point".

**2. Showing the Graph Cursor Values**

- At the edit graph window enter a callback function ("graphFunc") and click OK to exit and save changes.
- Generate the callback function.
- Go to the .c tab at the workspace and locate the callback function.
- Define 2 double variables in order to store the graph cursor values.:

*double x,y;*

- Assign the graph cursor values to the variables:

*GetGraphCursor (panelHandle, PANEL_GRAPH, 1, &x, &y);*

- Assign the variables values to a numeric controls:

*SetCtrlVal (panelHandle, PANEL_NUMERIC_X, x);*

*SetCtrlVal (panelHandle, PANEL_NUMERIC_Y, y);*

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