radius
Value giving the radius of the Pie Chart in the current units (default units are millimetres)
xcen
Value giving the X coordinate of the centre of the Pie Chart in user space coordinates
ycen
Value giving the Y coordinate of the centre of the Pie Chart in user space coordinates
Description
The routine ggSetPieChartFrame() defines a Pie Chart frame with radius radius and centre at the point (xcen,ycen). The default Pie Chart frame, used if ggSetPieChartFrame() is not called before drawing a Pie Chart, gives a radius and a centre calculated to fit the available drawing area or current window.
If ggSetPieChartFrame() has been used, automatic sizing and positioning can be restored using the routine ggRestorePieChartSettings(). The frame can be redefined at any point in the user program by another call to ggSetPieChartFrame().
