| 
	    plenv
	  ( | xmin, | 
| xmax, | |
| ymin, | |
| ymax, | |
| just, | |
| axis ); | 
      Sets up plotter environment for simple graphs by calling pladv
      and setting up viewport and window to sensible default values.
      plenv leaves a standard margin (left-hand margin of eight character
      heights, and a margin around the other three sides of five character
      heights) around most graphs for axis labels and a title.  When these
      defaults are not suitable, use the individual routines plvpas,
      plvpor, or plvasp for setting up the viewport, plwind for
      defining the window, and plbox for drawing the box.
    
xmin
	  (PLFLTValue of x at left-hand edge of window (in world coordinates).
xmax
	  (PLFLTValue of x at right-hand edge of window (in world coordinates).
ymin
	  (PLFLTValue of y at bottom edge of window (in world coordinates).
ymax
	  (PLFLTValue of y at top edge of window (in world coordinates).
just
	  (PLINTControls how the axes will be scaled:
		  -1: the scales
		  will not be set, the user must set up the scale before calling
		  plenv using plsvpa, plvasp or other.
		
		  0: the x and
		  y axes are scaled independently to use as much of the screen as
		  possible.
		
		  1: the scales of
		  the x and y axes are made equal.
		
		  2: the axis of
		  the x and y axes are made equal, and the plot box will be square.
		
axis
	  (PLINTControls drawing of the box around the plot:
		  -2: draw no box, no tick marks, no
		  numeric tick labels, no axes.
		
		  -1: draw box only.
		
		  0: draw box, ticks, and numeric tick labels.
		
		  1: also draw coordinate axes at
		  x=0 and y=0.
		
		  2: also draw a grid at major tick
		  positions in both coordinates.
		
		  3: also draw a grid at minor tick
		  positions in both coordinates.
		
		  10: same as 0 except logarithmic
		  x tick marks. (The x
		  data have to be converted to logarithms separately.)
		
		  11: same as 1 except logarithmic
		  x tick marks. (The x
		  data have to be converted to logarithms separately.)
		
		  12: same as 2 except logarithmic
		  x tick marks. (The x
		  data have to be converted to logarithms separately.)
		
		  13: same as 3 except logarithmic
		  x tick marks. (The x
		  data have to be converted to logarithms separately.)
		
		  20: same as 0 except logarithmic
		  y tick marks. (The y
		  data have to be converted to logarithms separately.)
		
		  21: same as 1 except logarithmic
		  y tick marks. (The y
		  data have to be converted to logarithms separately.)
		
		  22: same as 2 except logarithmic
		  y tick marks. (The y
		  data have to be converted to logarithms separately.)
		
		  23: same as 3 except logarithmic
		  y tick marks. (The y
		  data have to be converted to logarithms separately.)
		
		  30: same as 0 except logarithmic
		  x and y tick marks. (The x and y
		  data have to be converted to logarithms separately.)
		
		  31: same as 1 except logarithmic
		  x and y tick marks. (The x and y
		  data have to be converted to logarithms separately.)
		
		  32: same as 2 except logarithmic
		  x and y tick marks. (The x and y
		  data have to be converted to logarithms separately.)
		
		  33: same as 3 except logarithmic
		  x and y tick marks. (The x and y
		  data have to be converted to logarithms separately.)
		
		  40: same as 0 except date / time
		  x labels.
		
		  41: same as 1 except date / time
		  x labels.
		
		  42: same as 2 except date / time
		  x labels.
		
		  43: same as 3 except date / time
		  x labels.
		
		  50: same as 0 except date / time
		  y labels.
		
		  51: same as 1 except date / time
		  y labels.
		
		  52: same as 2 except date / time
		  y labels.
		
		  53: same as 3 except date / time
		  y labels.
		
		  60: same as 0 except date / time
		  x and y labels.
		
		  61: same as 1 except date / time
		  x and y labels.
		
		  62: same as 2 except date / time
		  x and y labels.
		
		  63: same as 3 except date / time
		  x and y labels.
		
		  70: same as 0 except custom
		  x and y labels.
		
		  71: same as 1 except custom
		  x and y labels.
		
		  72: same as 2 except custom
		  x and y labels.
		
		  73: same as 3 except custom
		  x and y labels.
		
      Redacted form: plenv(xmin, xmax, ymin, ymax, just, axis)
    
This function is used in example 1,3,9,13,14,19-22,29.