You must add the plplot_octave script installation directory to Octave
LOADPATH *before* the standard Octave LOADPATH. The best way to do this
is to create a .octaverc file in your home directory. By default

LOADPATH ="<install-directory>/share/plplot_octave//:"

If you also want to use Octave's standard plotting package, gnuplot, you
must set LOADPATH as:

LOADPATH ="<install-directory>/share/plplot_octave//:\
	<install-directory>/share/octave//:"

and use the command "toggle_plplot_use" to switch between the two plot packages.
Read the INSTALL file for more details.

Then, invoke Octave and create a vector, say

	octave:1> x=-pi:0.1:pi;

and plot it

	plot(x,sin(x))

change the legend:

	plot(x,sin(x),';Sin(x);')

set the title and plot data points
	
	title "My first plot";
	plot(x,sin(x),'-o;Sin(x);')

change the legend position

	legend ("opaque",0.8,0.5);
	plot(x,sin(x),';Sin(x);');

save you plot in color postscript

	save_fig ("~/sin.ps","psc")

and see the result
	
	system("gv ~/sin.ps")

create a new plot window using the tk driver

	fig(1,"tk")

Use uper an subscript in captions

	title("Sin(x#u2#d)")
	plot(x,sin(x),'-o;Sin(x#u2#d);',x,cos(x),'y');

close the previous window

	closefig(0)

read the online help

	help plot
	help __pl_opt

and try it! Bellow is a short description of the available commands.
You also have access to the PLplot API, 

	help plfill

		plfill(x, y)

		   Original PLplot call documentation:

		   plfill(n, x, y) ...

NOTES: - You don't need to specify vector or matrix dimensions.
       - When setting Octave variable "automatic_replot = 1", changes take
	 effect immediately, otherwise they only take effect at the next plot.
	 (This does not yet apply to all plot types).


--- Plot window control
fig,
figure		-- Set the current plot window or creates a new one.

closefig	-- Close a plot window.
closeallfig	-- Close all plot windows.

free_fig	-- Return the number of an unused plot figure.

save_fig	-- Save or prints the current plot figure.
lp_setup	-- Set printer command and options for use with `save_fig'.

--- 2D Plots
loglog,
semilogx,
semilogy,	-- Make 2D plots in log scales.
plot		-- Plot scalar, vector or matrices in various point and line styles.
mplot		-- Plot multiple plots per figure.
polar		-- Make a 2D polar plot.
contour		-- Draws a contour plot.
shade		-- Shaded/contour plot of matrix.
label_plot	-- Plot data with point style, marking each point with a number or label.
fill 		-- Draw filled 2-D polygons.
arrows		-- Plot an array of arrows.

--- 3D plots
mesh		-- Mesh surface plot.
meshc		-- mesh() with contour at base xy plane.
meshz		-- mesh() with a courtain.
plot3		-- Three-dimensional analogue of plot.
surf		-- Surface plot
surfc		-- surf() with contour at base xy plane.
surfl		-- surf() with lighting.
shading		-- Specifies how the surface in the surf plots is done.

--- Plot control and decorations
top_title,
bottom_title	-- don't work in PLplot!
title		-- Defines a title for the next plot. 

ylabel,
xlabel,
zlabel		-- Defines a label for the x/y/z-axis of the next plot.

xticks,
yticks		-- set the x/yticks interval.

plot_border	-- Don't work in PLplot.
plot_margin	-- Set/return the status of the plot margin around the plot.

autostyle	-- If set increases line style after each plot. 
legend		-- Sets the legend position and mode.
grid		-- Turn on/off grid lines at major/minor ticks.

axis		-- Sets the axis limits, plot scales and axis decoration.
axis_set	-- Return current axis status.

plclg,
plclearplot	-- Clear the plot window.
fig_state	-- save/restore current figure axis and hold state.
shg		-- Show the graph window. 
stopdraw	-- Stop drawing plots, but still store them.
drawnow		-- Plot all stored plots.

--- Interative plots
stripc,
stripc_add,
stripc_del,	-- creates/plot/delete a four pen stripchart.
comet		-- Displays an animated comet plot of one the vector. 
plrb		-- Iteractively selects a rectangular region of the plot. 

--- Interative utilities
text		-- Place text on a 2-D graph at x y positions.
set_view 	-- Set up the altitude and azimute in degrees for posterior 3d plots.
arrow		-- Plot one arrow. 
zoom		-- Select left botton and right top area for setting axis.

--- Multiple plots
multiplot	-- Sets and resets multiplot mode. 	
oneplot		-- Switches from multiplot to single plot mode.
subplot		-- Sets plot in multiplot mode.
subwindow	-- Sets subwindow position in multiplot mode for next plot.

--- Colormaps and color utilities
blue, bone,
cool, green,
hot, copper,
pink, prism,
red, hsv, bgr	-- Several colormaps.

colormap	-- Set colormap1.
hls2rgb		-- Hue-lightness-saturation to red-green-blue conversion. 
rgb2hls		-- red-green-blue to hue-lightness-saturation conversion. 
rgbplot		-- Plot color map.

--- Interative mouse usage
ginput		-- Return the current mouse position in plot.
gtext		-- Place text on a 2-D graph using a mouse.

--- Utilities
clip 		-- Clip values outside the range to the value at the boundary of the range.
tdeblank	-- Remove trailing amd leading blanks from string.

--- Misc
pldef		-- set your defaults.
plsetopt	-- set/view/reset/aplly plplot options.
plimage		-- display octave images.
griddata	-- grid irregularly sampled data

toggle_plplot_use	-- use plplot or gnuplot.
plplot_octave_path	-- set or return octave_plplot scripts directory path.

plplot_stub	-- Definition of all implemented plplot API functions.
