c
c    The following routines are intended to make "nice" plots, i.e. line
c    thickness control, nice labeling, infinite control over the format
c    of axes, etc.  All of these routines write unto a standard UNIX
c    plot file and the actual plots are made by a call to the system
c    command plot (see plot(1) in the UNIX manual).
c
c    I  - The plot file.
c         
c         1.	The calling program must contain the following common block:
c		common /pfile/ ipunit
c		where ipunit is integer*4
c		The following common blocks MUST NOT be used since they are
c 		used internally by the plotting routines:
c			pdim, pscl,rbuf,ibuf
c		Also the following function routines must not be used since
c		they are used by the plotting routines:
c			xmap,ymap
c	  2.	The plot file can be given a name, but it must be opened
c		using the following fortran callable c routine:
c		call ropen(name, 1, ipunit)
c		where name is the plot file name (character string)
c		and   ipunit is the contents of common block pfile which
c		                is returned by ropen.
c	  3.	The plot file can be rewound using the following fortran
c		callable c routine:
c		call rseek(ipunit, 0, 0)
c	  4.	The source for the c io routines is in rawio.c
c         5.    In order to load the plotting routines simply include LIB
c               in the compilation statement.  There is a makefile in this
c               directory which will remake LIB if necessary.
c
c    II - The plot format.
c	  1.	All physical plot dimensions are relative to a versatek plot.
c	  2.	A single sheet of versatek paper is 11 inches wide and 8.5
c		inches tall.  The plotting area is 10 inches wide and 7.5
c		inches tall.  
c	  3.	There are two plot modes which relate to the basic orientation
c		of the plot:
c		1.	Normal mode - where the origin of the physical plot
c			dimensions is 0.5 inch above and to the right of the
c			lower left hand corner of the
c			versatek paper as it is oriented in the versatek.
c			Thus plots in this mode have their horizontal axis
c			along the long axis of the paper
c		2.	Transposed mode - where the origin of the physical plot
c			dimensions is 0.5 inch above and to the left of the
c			lower right hand corner of the versatek paper as it
c			is oriented in the versatek.  Thus plots in this
c			mode have their horizontal axis along the short
c			axis of the paper.
c	  4.	Plots are scaled up in size on the tektronix so that they fit
c		the 14.3 by 10.8 inch size of the tektronix screen.  Thus a
c		hard copy of a tektronix plot on the versatek should give the
c		same approximate physical dimensions as the same plot plotted
c		directly on the versatek.
c	  5.	The default size of plots on the hp plotter is the same as
c		that of the versatek.  The size of an hp plot can be scaled
c		up or down, though, by a call to xlimit (this call will not
c		affect the versatek or tektronix).
c
c    III- The general setup procedure.
c	  1.	After the plot file has been opened and positioned,
c		a call to initt MUST BE MADE BEFORE ANY OTHER PLOT
c		ROUTINES ARE CALLED.  Initt should only be called once
c		or when ever you rewind the plot file and rewrite
c		on it.
c	  2.	Calls to setdim and setscl must also be made prior to
c		calls to the actual plotting routines.
c
c
