15.0.12 `glib_window'
---------------------

glib_window(XMIN,YMIN,XMAX,YMAX)
     :   It generates a window with the left top corner [XMIN,YMIN] and
      the right bottom corner [XMAX,YMAX].    If the global variable
     GLIB_MATH_COORDINATE is set to 1, mathematical   coordinate system
     will be employed, i.e., the left top   corner will have the
     coordinate [XMIN,YMAX].
Example:
      glib_window(-1,-1,10,10);

