Gnuplot.Range
type t =
| X of float * float
| Y of float * float
| XY of float * float * float * float
arguments are x1, x2, y1, y2
| XYZ of float * float * float * float * float * float
arguments are x1, x2, y1, y2, z1, z2
| Date of date * date
| Time of time * time * timezone
| Local_time of time * time
Time range in local time zone.
*)Used for constructing ranges for the X axis, Y axis or both.