If you have Tcl/Tk installed, you can activate a widget-based menu for control of the graphical displays. This is the only approach that allows you to change the selection of the displays (add more or remove some) while the program is executing. Fig. 6 illustrates the add/delete widgets. The menu also allows you to rotate the view of 3D plots and change the density of isolines in the surface plots (Fig. 7). If gquiet is .false. (default), you can activate the widget by responding yes to both text prompts. If you have set gquiet to be .true., you can activate the menu by setting menuon to .true. and starting the menu manually with the command wish < grmenu &.
