
plvpas: Specify viewport using coordinates and aspect ratio 

DESCRIPTION:

    Device-independent routine for setting up the viewport.  The viewport
    is chosen to be the largest with the given aspect ratio that fits
    within the specified region (in terms of normalized subpage
    coordinates).  This routine is functionally equivalent to plvpor when
    a ``natural'' aspect ratio (0.0) is chosen.  Unlike plvasp, this
    routine reserves no extra space at the edges for labels. 

SYNOPSIS:

plvpas(xmin, xmax, ymin, ymax, aspect)

ARGUMENTS:

    xmin (PLFLT, input) :    The normalized subpage coordinate of the
    left-hand edge of the viewport. 

    xmax (PLFLT, input) :    The normalized subpage coordinate of the
    right-hand edge of the viewport. 

    ymin (PLFLT, input) :    The normalized subpage coordinate of the
    bottom edge of the viewport. 

    ymax (PLFLT, input) :    The normalized subpage coordinate of the top
    edge of the viewport. 

    aspect (PLFLT, input) :    Ratio of length of y axis to length of x
    axis. 
