Warning:
	I've hacked these libraries (all three) so that move() and
cont() use a float for the 'y' coordinate.  The original libraries
used ints for x and y.  The xplot library has been hacked, but the
internal guts, which really on X11 include files, stubbornly refuse
to write floats; it still writes ints.  (Note: I've changed xplot
back so that only a bare minimum of the library uses floats; the
fact that many calls are still ints is NOT the reason that it writes
ints; as I said, it writes ints because of the X11 header files,
which define XPoint as a structure containing ints.)
