xscale-class: Class "xscale"
Description
  An object of class "xscale" represents x-scale style.
Objects from the Class
Objects can be created by calls of the form 
  new("xscale", from, to, label, gp, draw). Slots
    from- A 
pos class, indicates the start point 
    postion of x-scale.  to- A 
pos class, indicates the end point 
    postion of x-scale.  label"character" the label of x-scale  gp- A 
"list" object, It will convert to an object of 
    class gpar. This is basically a list of graphical 
    parameter settings of x-scale.  draw- A 
"logical" value indicating whether the x-scale
    should be draw.