
plbox: Draw a box with axes, etc

DESCRIPTION:

    This function is used in examples 1,2,4,6,6-12,14-18,21,23-26,29. 

SYNOPSIS:

plbox(xopt, xtick, nxsub, yopt, ytick, nysub)

ARGUMENTS:

    xopt (const char *, input) :    Pointer to character string specifying
    options for horizontal axis.  The string can include any
    combination of the following letters (upper or lower case) in any
    order: a: Draws axis, X-axis is horizontal line (y=0), and Y-axis
    is vertical line (x=0). 
        b: Draws bottom (X) or left (Y) edge of frame. 
        c: Draws top (X) or right (Y) edge of frame. 
        d: Plot labels as date / time.  Values are assumed to be
        seconds since the epoch  (as used by gmtime). 
        f:    Always use fixed point numeric labels. 
        g: Draws a grid at the major tick interval. 
        h: Draws a grid at the minor tick interval. 
        i: Inverts tick marks, so they are drawn outwards, rather than
        inwards. 
        l: Labels axis logarithmically.  This only affects the labels,
        not the data, and so it is necessary to compute the logarithms
        of data points before passing them to any of the drawing
        routines. 
        m: Writes numeric labels at major tick intervals in the
        unconventional location (above box for X, right of box for Y). 
        n: Writes numeric labels at major tick intervals in the
        conventional location (below box for X, left of box for Y). 
        o: Use custom labelling function to generate axis label text. 
        The custom labelling function can be defined with the
        plslabelfunc command. 
        s: Enables subticks between major ticks, only valid if t is
        also specified. 
        t: Draws major ticks. 
        u: Exactly like "b" except don't draw edge line. 
        w: Exactly like "c" except don't draw edge line. 
        x: Exactly like "t" (including the side effect of the
        numerical labels for the major ticks) except exclude drawing
        the major and minor tick marks. 


    xtick (PLFLT, input) :    World coordinate interval between major
    ticks on the x axis. If it is set to zero, PLplot automatically
    generates a suitable tick interval. 

    nxsub (PLINT, input) :    Number of subintervals between major x axis
    ticks for minor ticks.    If it is set to zero, PLplot automatically
    generates a suitable minor tick interval. 

    yopt (const char *, input) :    Pointer to character string specifying
    options for vertical axis.  The string can include any combination
    of the letters defined above for xopt, and in addition may
    contain: v: Write numeric labels for vertical axis parallel to the
    base of the graph, rather than parallel to the axis. 


    ytick (PLFLT, input) :    World coordinate interval between major
    ticks on the y axis. If it is set to zero, PLplot automatically
    generates a suitable tick interval. 

    nysub (PLINT, input) :    Number of subintervals between major y axis
    ticks for minor ticks.    If it is set to zero, PLplot automatically
    generates a suitable minor tick interval. 
