Re: [gtkextra] Traversing through data points and displaying the value

[Michael N. <mn...@sp...>]

> I was wondering if there is a simple way using the GtkExtra library to
> be able to click at a point in the graph and then by using cursors or
> some other way to traverse from one point to the next and get the y &
> x values as you go along.

Using S-Lang as pseudo-code, add a signal handler for motion events

      ... = g_signal_connect(canvas,"motion_notify_event", ...

to the canvas, and within the handler do something like

     gtk_widget_get_pointer(canvas, &x, &y);
     gtk_plot_get_point(plot, x, y, &x, &y);

and display it how you wish, such as in a label

     gtk_label_set_text(label, sprintf("( %5.3f, %5.3f )", x, y));

HTH,
-Mike