15.64.30.1  Options  - 

     1.  ON - Draws horizontal, vertical, and Z lines.
     2.  OFF - No grid is drawn.  (Default)
     3.  Y|HORIZONTAL - Draws horizontal lines at Y major tics.
     4.  X|VERTICAL - Draws vertical lines at X major tics.
     5.  Z - Draws line perpendicular to Z at Z major tics.
     6.  :XY - Draws lines in XY plane.
     7.  YZ - Draws lines in YZ plane when THREE=ON.
     8.  ZX - Draws lines in ZX plane when THREE=ON.
         If XY,YZ,ZX are not specified, then all 3 are assumed to be on.
     9.  CYCLE  -  Draws  the grid lines corresponding to Z major ticks in
         different  colors,  textures...   according  to  the  SET   CYCLE
         command.  (Default:OFF)
    10.  OUTLINE - Draws outline around 3-d grid.  (Default:OFF)
    11.  INTENSITY  -  Sets  line  intensity  or  width (0-5).  0 gets the
         intensity from the SET INTENSITY or SET AXES command.
    12.  WHITE...  - Sets the line color.  (Default:Same as axes)
    13.  SOLID...   -  Sets  the  line  texture.   (Default:Same  as axes)
         See:Command SET TEXTURE.
    14.  SYMBOL  -  Draws  a symbol [sym] to be plotted at intersection of
         vertical and horizontal lines.  (Default:sym=0O)
    15.  SIZE  -  sets the size of the grid symbols If the size is not set
         then it is adjusted automatically by the window size.
    16.  THETA,PHI - specify the normal to the grid symbol for 3-d plots.
    17.  ANGLE - rotates the symbol around the normal for 3-d plots.
    18.  PERMANENT - Sets the current grid options permanently for all NEW
         plots.
If  no  options  are  specified, then all grid parameters are reset to the
original defaults.
(Default:OFF SYM='0O' INTEN=0 NOCOLOR NOTEXTURE THETA=0 PHI=0 ANGLE=0)