plot:

Synopsis: RLaB graphics interface

Syntax: plot ( A )
	plot ( A , KEY )

Description:

	Plot A in the current sub-plot in the current plot-window.  A
	can be a matrix, in which case the columns are plotted against
	the 1st column. If A is a column vector, then the column is
	plotted versus the row values. A can also be a list, in which
	case each matrix in the list is plotted (this is a good way to
	plot data with different scales). If A is a list the elements
	of the list with names that can be converted to decimal are
	plotted first, in ascending numerical order. the list elements
	with names that cannot be converted to decimal are plotted
	last, in ascending string order.

	KEY is an optional argument denoting the column to use as the
	independent variable. 

		if KEY > 0	Use KEY as the independent variable on
				the X-axis.

		if KEY = 0	Plot all columns of A against the row
				indices. 

		if KEY < 0	Use abs(KEY) as the independent
				variable on the Y-axis.

	Plot and its related functions define a user interface to the
	Plplot graphics library. The PLPLOT graphics library can
	produce output on X-windows, DOS, OS/2, Amiga, Tektronix,
	PostScipt, and other output devices.

	The plot interface operation is based upon two important
	concepts: the current plot-window, and the current sub-plot.

	The current plot-window is a valid concept only if selected
	output device supports multiple windows (X-windows for
	example).

	The current sub-plot should be available for all devices,
	since sub-plots are individual plots that co-exist on the same
	page, or display.

	Invoking pstart() will create a plot-window. The newly created
	plot-window will be the current plot-window. If more than one
	plot-window has been created, then the current window can be
	selected with the pwin() function. The current plot-window can
	be closed with pclose(). All of the plot-windows can be closed
	with pend().

	Each plot-window can be divided up into more than 1 sub-plot
	(the default). The number and arrangement of the sub-plots is
	specified by the user when pstart() is invoked. All plot
	manipulation functions, such as plstyle(), plgrid(), xlabel(),
	etc... work on the current sub-plot. When plot() is used the
	current sub-plot is created, after which the current sub-plot
	is incremented. The sub-plots are incremented to the right,
	and down (the same way you read an English language book).

	The following is a list of the plot related functions.

	pstart ( NCOL, NROW, DEVICE )
	pwin ( NWIN )
	showpwin ( )
	pclose ( )
	pend ( )

	plot ( DATA )
	plhist ( DATA )
	plhistx ( DATA )
	plerry ( X, Y, Ymin, Ymax )
	xlabel ( XLABEL )
	ylabel ( YLABEL )
	ptitle ( PTITLE )
	plimits ( XMIN, XMAX, YMIN, YMAX, ZMIN, ZMAX )
	plgrid ( GRID_STY_X, GRID_STY_Y )
	plgrid3 ( GRID_STY_X, GRID_STY_Y, GRID_STY_Z )
	plaxis ( X_STR, Y_STR )
	plstyle ( PSTYLE )
	plaspect ( ASPECT )
	subplot ( N )

	plot3 ( L3D )
	plmesh ( L3D )
	plcont ( CL )
	zlabel ( ZLABEL )
	plalt ( ALT )
	plaz ( AZ )

	plfont ( FONT )
	plwid ( WIDTH )
	plptex ( TEXT, X, Y, DX, DY, JUST )
	plegend ( DESCRIPTION )

	plprint ( FILENM, DEVICE )
	replot ( )

	plscol0 ( COLOR, RED, GREEN, BLUE )
	
	The high-level plot functions are implemented in RLaB. The
	low-level plot functions mimic the Plplot application
	programming interface (API). This particular method of
	implementation was chosen to allow users maximum flexibility
	when adding new or improved plot features.

	The low-level Plplot functions all begin with a `_'
	character. One low-level function of use to some is
	_plflush. This function takes no arguments, and flushes the
	plot buffer, if the plot device supports that function.
