Syntax: LIMITS pexpr pexpr
or      LIMITS pexpr Y1 Y2
or      LIMITS X1 X2 pexpr
or      LIMITS X1 X2 Y1 Y2

   (`Pexpr' is the name of a vector, or an expression in parentheses,
e.g. LIMITS 0 10 (lg(y - 2)) )

   LIMITS sets the coordinates of the plot region. All coordinates in
RELOCATE, DRAW, etc, are referred to these limits. The arguments to
LIMITS specify explicit limits for the x or y axis (X1 X2 or Y1 Y2),
or default (specify a parenthesised expression, or the name of the
vector to be used).

   The limits used are to be found in the variables $fx1, $fx2, $fy1,
and $fy2. These are slightly weird variables --- see the discussion
under DEFINE name |.

