It is assumed this task will only plot HK or AUX and GTI data for
the PPS processing. It has been made general enough to plot any non-
string parameters from any file.
The task defaults to plotting a TIME column if no value for
parameter ``xcolumnname'' is entered.
The task defaults to writing a postscript plot, but in principle
can accept any pgplot compatible device, which also lends this task to
producing interactive plots at some later stage.
This task supports vertical (portrait) as well as the default
landscape plots. This is accomplished by entering the value ``/VPS''
as the plot device instead of ``/PS''.