--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doc/interpreter/plot.txi	Tue Oct 19 10:08:42 1999 +0000
@@ -0,0 +1,747 @@
+@c Copyright (C) 1996, 1997 John W. Eaton
+@c This is part of the Octave manual.
+@c For copying conditions, see the file gpl.texi.
+
+@node Plotting, Matrix Manipulation, Input and Output, Top
+@chapter Plotting
+
+All of Octave's plotting functions use @code{gnuplot} to handle the
+actual graphics.  There are two low-level functions, @code{gplot} and
+@code{gsplot}, that behave almost exactly like the corresponding
+@code{gnuplot} functions @code{plot} and @code{splot}.  A number of
+other higher level plotting functions, patterned after the graphics
+functions found in @sc{Matlab} version 3.5, are also available.
+These higher level functions are all implemented in terms of the two
+low-level plotting functions.
+
+@menu
+* Two-Dimensional Plotting::    
+* Specialized Two-Dimensional Plots::  
+* Three-Dimensional Plotting::  
+* Plot Annotations::            
+* Multiple Plots on One Page::  
+@end menu
+
+@node Two-Dimensional Plotting, Specialized Two-Dimensional Plots, Plotting, Plotting
+@section Two-Dimensional Plotting
+
+@deffn {Command} gplot @var{ranges} @var{expression} @var{using} @var{title} @var{style}
+Generate a 2-dimensional plot.
+
+The @var{ranges}, @var{using}, @var{title}, and @var{style} arguments
+are optional, and the @var{using}, @var{title} and @var{style}
+qualifiers may appear in any order after the expression.  You may plot
+multiple expressions with a single command by separating them with
+commas.  Each expression may have its own set of qualifiers.
+
+The optional item @var{ranges} has the syntax
+
+@example
+[ x_lo : x_up ] [ y_lo : y_up ]
+@end example
+
+@noindent
+and may be used to specify the ranges for the axes of the plot,
+independent of the actual range of the data.  The range for the y axes
+and any of the individual limits may be omitted.  A range @code{[:]}
+indicates that the default limits should be used.  This normally means
+that a range just large enough to include all the data points will be
+used.
+
+The expression to be plotted must not contain any literal matrices
+(e.g. @code{[ 1, 2; 3, 4 ]}) since it is nearly impossible to
+distinguish a plot range from a matrix of data.
+
+See the help for @code{gnuplot} for a description of the syntax for the
+optional items.
+
+By default, the @code{gplot} command plots the second column of a matrix
+versus the first.  If the matrix only has one column, it is taken as a
+vector of y-coordinates and the x-coordinate is taken as the element
+index, starting with zero.  For example,
+
+@example
+gplot rand (100,1) with linespoints
+@end example
+
+@noindent
+will plot 100 random values and connect them with lines.  When
+@code{gplot} is used to plot a column vector, the indices of the
+elements are taken as x values.
+
+  If there are more than two columns, you can
+choose which columns to plot with the @var{using} qualifier. For
+example, given the data
+
+@example
+x = (-10:0.1:10)';
+data = [x, sin(x), cos(x)];
+@end example
+
+@noindent
+the command
+
+@example
+gplot [-11:11] [-1.1:1.1] \
+  data with lines, data using 1:3 with impulses
+@end example
+
+@noindent
+will plot two lines.  The first line is generated by the command
+@code{data with lines}, and is a graph of the sine function over the
+range @minus{}10 to 10.  The data is taken from the first two columns of
+the matrix because columns to plot were not specified with the
+@var{using} qualifier.
+
+The clause @code{using 1:3} in the second part of this plot command
+specifies that the first and third columns of the matrix @code{data}
+should be taken as the values to plot.
+
+In this example, the ranges have been explicitly specified to be a bit
+larger than the actual range of the data so that the curves do not touch
+the border of the plot.
+@end deffn
+
+@deffn {Command} gset options
+@deffnx {Command} gshow options
+@deffnx {Command} replot options
+In addition to the basic plotting commands, the whole range of
+@code{gset} and @code{gshow} commands from @code{gnuplot} are available,
+as is @code{replot}.
+
+@findex set
+@findex show
+Note that in Octave 2.0, the @code{set} and @code{show} commands were
+renamed to @code{gset} and @code{gshow} in order to allow for
+compatibility with the @sc{Matlab} graphics and GUI commands in a future
+version of Octave.  (For now, the old @code{set} and @code{show}
+commands do work, but they print an annoying warning message to try to
+get people to switch to using @code{gset} and @code{gshow}.)
+
+The @code{gset} and @code{gshow} commands allow you to set and show
+@code{gnuplot} parameters.  For more information about the @code{gset}
+and @code{gshow} commands, see the documentation for @code{set} and
+@code{show} in the @code{gnuplot} user's guide (also available on line
+if you run @code{gnuplot} directly, instead of running it from Octave).
+
+The @code{replot} command allows you to force the plot to be
+redisplayed.  This is useful if you have changed something about the
+plot, such as the title or axis labels.  The @code{replot} command also
+accepts the same arguments as @code{gplot} or @code{gsplot} (except for
+data ranges) so you can add additional lines to existing plots.  
+
+For example,
+
+@example
+gset term tek40
+gset output "/dev/plotter"
+gset title "sine with lines and cosine with impulses"
+replot "sin (x) w l"
+@end example
+
+will change the terminal type for plotting, add a title to the current
+plot, add a graph of
+@iftex
+@tex
+$\sin(x)$
+@end tex
+@end iftex
+@ifinfo
+sin (x) 
+@end ifinfo
+to the plot, and force the new plot to be
+sent to the plot device.  This last step is normally required in order
+to update the plot.  This default is reasonable for slow terminals or
+hardcopy output devices because even when you are adding additional
+lines with a replot command, gnuplot always redraws the entire plot, and
+you probably don't want to have a completely new plot generated every
+time something as minor as an axis label changes.
+
+@findex shg
+The command @code{shg} is equivalent to executing @code{replot} without
+any arguments.
+@end deffn
+
+@defvr {Built-in Variable} automatic_replot
+You can tell Octave to redisplay the plot each time anything about it
+changes by setting the value of the builtin variable
+@code{automatic_replot} to a nonzero value.  Since this is fairly
+inefficient, the default value is 0.
+@end defvr
+
+Note that NaN values in the plot data are automatically omitted, and
+Inf values are converted to a very large value before calling gnuplot.
+
+@c XXX FIXME XXX -- add info about what to do to get plots on remote X
+@c terminals.  People often forget how to properly set DISPLAY and run
+@c xhost.
+
+@c XXX FIXME XXX -- add info about getting paper copies of plots.
+
+The @sc{Matlab}-style two-dimensional plotting commands are:
+
+@cindex plotting
+@cindex graphics
+
+@deftypefn {Function File} {} plot (@var{args})
+This function produces two-dimensional plots.  Many different
+combinations of arguments are possible.  The simplest form is
+
+@example
+plot (@var{y})
+@end example
+
+@noindent
+where the argument is taken as the set of @var{y} coordinates and the
+@var{x} coordinates are taken to be the indices of the elements,
+starting with 1.
+
+If more than one argument is given, they are interpreted as
+
+@example
+plot (@var{x}, @var{y}, @var{fmt} ...)
+@end example
+
+@noindent
+where @var{y} and @var{fmt} are optional, and any number of argument
+sets may appear.  The @var{x} and @var{y} values are
+interpreted as follows:
+
+@itemize @bullet
+@item
+If a single data argument is supplied, it is taken as the set of @var{y}
+coordinates and the @var{x} coordinates are taken to be the indices of
+the elements, starting with 1.
+
+@item
+If the first argument is a vector and the second is a matrix, the
+the vector is plotted versus the columns (or rows) of the matrix.
+(using whichever combination matches, with columns tried first.)
+
+@item
+If the first argument is a matrix and the second is a vector, the
+the columns (or rows) of the matrix are plotted versus the vector.
+(using whichever combination matches, with columns tried first.)
+
+@item
+If both arguments are vectors, the elements of @var{y} are plotted versus
+the elements of @var{x}.
+
+@item
+If both arguments are matrices, the columns of @var{y} are plotted
+versus the columns of @var{x}.  In this case, both matrices must have
+the same number of rows and columns and no attempt is made to transpose
+the arguments to make the number of rows match.
+
+If both arguments are scalars, a single point is plotted.
+@end itemize
+
+The @var{fmt} argument, if present is interpreted as follows.  If
+@var{fmt} is missing, the default gnuplot line style is assumed.
+
+@table @samp
+@item -
+Set lines plot style (default).
+
+@item .
+Set dots plot style.
+
+@item @@
+Set points plot style.
+
+@item -@@
+Set linespoints plot style.
+
+@item ^
+Set impulses plot style.
+
+@item L
+Set steps plot style.
+
+@item #
+Set boxes plot style.
+
+@item ~
+Set errorbars plot style.
+
+@item #~
+Set boxerrorbars plot style.
+
+@item @var{n}
+Interpreted as the plot color if @var{n} is an integer in the range 1 to
+6.
+
+@item @var{nm}
+If @var{nm} is a two digit integer and @var{m} is an integer in the
+range 1 to 6, @var{m} is interpreted as the point style.  This is only
+valid in combination with the @code{@@} or @code{-@@} specifiers.
+
+@item @var{c}
+If @var{c} is one of @code{"r"}, @code{"g"}, @code{"b"}, @code{"m"},
+@code{"c"}, or @code{"w"}, it is interpreted as the plot color (red,
+green, blue, magenta, cyan, or white).
+
+@item +
+@itemx *
+@itemx o
+@itemx x
+Used in combination with the points or linespoints styles, set the point
+style.
+@end table
+
+The color line styles have the following meanings on terminals that
+support color.
+
+@example
+Number  Gnuplot colors  (lines)points style
+  1       red                   *
+  2       green                 +
+  3       blue                  o
+  4       magenta               x
+  5       cyan                house
+  6       brown            there exists
+@end example
+
+Here are some plot examples:
+
+@example
+plot (x, y, "@@12", x, y2, x, y3, "4", x, y4, "+")
+@end example
+
+This command will plot @code{y} with points of type 2 (displayed as
+@samp{+}) and color 1 (red), @code{y2} with lines, @code{y3} with lines of
+color 4 (magenta) and @code{y4} with points displayed as @samp{+}.
+
+@example
+plot (b, "*")
+@end example
+
+This command will plot the data in the variable @code{b} will be plotted
+with points displayed as @samp{*}.
+@end deftypefn
+
+@deftypefn {Function File} {} hold @var{args}
+Tell Octave to `hold' the current data on the plot when executing
+subsequent plotting commands.  This allows you to execute a series of
+plot commands and have all the lines end up on the same figure.  The
+default is for each new plot command to clear the plot device first.
+For example, the command
+
+@example
+hold on
+@end example
+
+@noindent
+turns the hold state on.  An argument of @code{off} turns the hold state
+off, and @code{hold} with no arguments toggles the current hold state.
+@end deftypefn
+
+@deftypefn {Function File} {} ishold
+Return 1 if the next line will be added to the current plot, or 0 if
+the plot device will be cleared before drawing the next line.
+@end deftypefn
+
+@deftypefn {Function File} {} clearplot
+@deftypefnx {Function File} {} clg
+Clear the plot window and any titles or axis labels.  The name
+@code{clg} is aliased to @code{clearplot} for compatibility with @sc{Matlab}.
+
+The commands @kbd{gplot clear}, @kbd{gsplot clear}, and @kbd{replot
+clear} are equivalent to @code{clearplot}.  (Previously, commands like
+@kbd{gplot clear} would evaluate @code{clear} as an ordinary expression
+and clear all the visible variables.)
+@end deftypefn
+
+@deftypefn {Function File} {} closeplot
+Close stream to the @code{gnuplot} subprocess.  If you are using X11,
+this will close the plot window.
+@end deftypefn
+
+@deftypefn {Function File} {} purge_tmp_files
+Delete the temporary files created by the plotting commands.
+
+Octave creates temporary data files for @code{gnuplot} and then sends
+commands to @code{gnuplot} through a pipe.  Octave will delete the
+temporary files on exit, but if you are doing a lot of plotting you may
+want to clean up in the middle of a session.
+
+A future version of Octave will eliminate the need to use temporary
+files to hold the plot data.
+@end deftypefn
+
+@deftypefn {Function File} {} axis (@var{limits})
+Sets the axis limits for plots.
+
+The argument @var{limits} should be a 2, 4, or 6 element vector.  The
+first and second elements specify the lower and upper limits for the x
+axis.  The third and fourth specify the limits for the y axis, and the
+fifth and sixth specify the limits for the z axis.
+
+With no arguments, @code{axis} turns autoscaling on.
+
+If your plot is already drawn, then you need to use @code{replot} before
+the new axis limits will take effect.  You can get this to happen
+automatically by setting the built-in variable @code{automatic_replot}
+to a nonzero value.
+@end deftypefn
+
+@node Specialized Two-Dimensional Plots, Three-Dimensional Plotting, Two-Dimensional Plotting, Plotting
+@section Specialized Two-Dimensional Plots
+
+@deftypefn {Function File} {} bar (@var{x}, @var{y})
+Given two vectors of x-y data, @code{bar} produces a bar graph.
+
+If only one argument is given, it is taken as a vector of y-values
+and the x coordinates are taken to be the indices of the elements.
+
+If two output arguments are specified, the data are generated but
+not plotted.  For example,
+
+@example
+bar (x, y);
+@end example
+
+@noindent
+and
+
+@example
+[xb, yb] = bar (x, y);
+plot (xb, yb);
+@end example
+
+@noindent
+are equivalent.
+@end deftypefn
+
+@deftypefn {Function File} {} contour (@var{z}, @var{n}, @var{x}, @var{y})
+Make a contour plot of the three-dimensional surface described by
+@var{z}.  Someone needs to improve @code{gnuplot}'s contour routines
+before this will be very useful.
+@end deftypefn
+
+@deftypefn {Function File} {} hist (@var{y}, @var{x})
+Produce histogram counts or plots.
+
+With one vector input argument, plot a histogram of the values with
+10 bins.  The range of the histogram bins is determined by the range
+of the data.
+
+Given a second scalar argument, use that as the number of bins.
+
+Given a second vector argument, use that as the centers of the bins,
+with the width of the bins determined from the adjacent values in
+the vector.
+
+Extreme values are lumped in the first and last bins.
+
+With two output arguments, produce the values @var{nn} and @var{xx} such
+that @code{bar (@var{xx}, @var{nn})} will plot the histogram.
+@end deftypefn
+
+@deftypefn {Function File} {} loglog (@var{args})
+Make a two-dimensional plot using log scales for both axes.  See the
+description of @code{plot} above for a description of the arguments that
+@code{loglog} will accept.
+@end deftypefn
+
+@deftypefn {Function File} {} polar (@var{theta}, @var{rho})
+Make a two-dimensional plot given polar the coordinates @var{theta} and
+@var{rho}.
+@end deftypefn
+
+@deftypefn {Function File} {} semilogx (@var{args})
+Make a two-dimensional plot using a log scale for the @var{x} axis.  See
+the description of @code{plot} above for a description of the arguments
+that @code{semilogx} will accept.
+@end deftypefn
+
+@deftypefn {Function File} {} semilogy (@var{args})
+Make a two-dimensional plot using a log scale for the @var{y} axis.  See
+the description of @code{plot} above for a description of the arguments
+that @code{semilogy} will accept.
+@end deftypefn
+
+@deftypefn {Function File} {} stairs (@var{x}, @var{y})
+Given two vectors of x-y data, bar produces a `stairstep' plot.
+
+If only one argument is given, it is taken as a vector of y-values
+and the x coordinates are taken to be the indices of the elements.
+
+If two output arguments are specified, the data are generated but
+not plotted.  For example,
+
+@example
+stairs (x, y);
+@end example
+
+@noindent
+and
+
+@example
+[xs, ys] = stairs (x, y);
+plot (xs, ys);
+@end example
+
+@noindent
+are equivalent.
+@end deftypefn
+
+@node Three-Dimensional Plotting, Plot Annotations, Specialized Two-Dimensional Plots, Plotting
+@section Three-Dimensional Plotting
+
+@deffn {Command} gsplot @var{ranges} @var{expression} @var{using} @var{title} @var{style}
+Generate a 3-dimensional plot.
+
+The @var{ranges}, @var{using}, @var{title}, and @var{style} arguments
+are optional, and the @var{using}, @var{title} and @var{style}
+qualifiers may appear in any order after the expression.  You may plot
+multiple expressions with a single command by separating them with
+commas.  Each expression may have its own set of qualifiers.
+
+The optional item @var{ranges} has the syntax
+
+@example
+[ x_lo : x_up ] [ y_lo : y_up ] [ z_lo : z_up ]
+@end example
+
+@noindent
+and may be used to specify the ranges for the axes of the plot,
+independent of the actual range of the data.  The range for the y and z
+axes and any of the individual limits may be omitted.  A range
+@code{[:]} indicates that the default limits should be used.  This
+normally means that a range just large enough to include all the data
+points will be used.
+
+The expression to be plotted must not contain any literal matrices (e.g.
+@code{[ 1, 2; 3, 4 ]}) since it is nearly impossible to distinguish a
+plot range from a matrix of data.
+
+See the help for @code{gnuplot} for a description of the syntax for the
+optional items.
+
+By default, the @code{gsplot} command plots each column of the
+expression as the z value, using the row index as the x value, and the
+column index as the y value.  The indices are counted from zero, not
+one.  For example,
+
+@example
+gsplot rand (5, 2)
+@end example
+
+@noindent
+will plot a random surface, with the x and y values taken from the row
+and column indices of the matrix.
+
+If parametric plotting mode is set (using the command
+@kbd{gset parametric}, then @code{gsplot} takes the columns of the
+matrix three at a time as the x, y and z values that define a line in
+three space.  Any extra columns are ignored, and the x and y values are
+expected to be sorted.  For example, with @code{parametric} set, it
+makes sense to plot a matrix like
+@iftex
+@tex
+$$
+\left[\matrix{
+1 & 1 & 3 & 2 & 1 & 6 & 3 & 1 & 9 \cr
+1 & 2 & 2 & 2 & 2 & 5 & 3 & 2 & 8 \cr
+1 & 3 & 1 & 2 & 3 & 4 & 3 & 3 & 7}\right]
+$$
+@end tex
+@end iftex
+@ifinfo
+
+@example
+1 1 3 2 1 6 3 1 9
+1 2 2 2 2 5 3 2 8
+1 3 1 2 3 4 3 3 7
+@end example
+@end ifinfo
+
+@noindent
+but not @code{rand (5, 30)}.
+@end deffn
+
+The @sc{Matlab}-style three-dimensional plotting commands are:
+
+@deftypefn {Function File} {} mesh (@var{x}, @var{y}, @var{z})
+Plot a mesh given matrices @code{x}, and @var{y} from @code{meshdom} and
+a matrix @var{z} corresponding to the @var{x} and @var{y} coordinates of
+the mesh.
+@end deftypefn
+
+@deftypefn {Function File} {} meshdom (@var{x}, @var{y})
+Given vectors of @var{x} and @var{y} coordinates, return two matrices
+corresponding to the @var{x} and @var{y} coordinates of the mesh.
+
+See the file @file{sombrero.m} for an example of using @code{mesh} and
+@code{meshdom}.
+@end deftypefn
+
+@defvr {Built-in Variable} gnuplot_binary
+The name of the program invoked by the plot command.  The default value
+is @code{"gnuplot"}.  @xref{Installation}.
+@end defvr
+
+@defvr {Built-in Variable} gnuplot_has_frames
+If the value of this variable is nonzero, Octave assumes that your copy
+of gnuplot has support for multiple frames that is included in recent
+3.6beta releases.  It's initial value is determined by configure, but it
+can be changed in your startup script or at the command line in case
+configure got it wrong, or if you upgrade your gnuplot installation.
+@end defvr
+
+@deftypefn {Function File} {} figure (@var{n})
+Set the current plot window to plot window @var{n}.  This function
+currently requires X11 and a version of gnuplot that supports multiple
+frames.
+@end deftypefn
+
+@defvr {Built-in Variable} gnuplot_has_multiplot
+If the value of this variable is nonzero, Octave assumes that your copy
+of gnuplot has the multiplot support that is included in recent
+3.6beta releases.  It's initial value is determined by configure, but it
+can be changed in your startup script or at the command line in case
+configure got it wrong, or if you upgrade your gnuplot installation.
+@end defvr
+
+@node Plot Annotations, Multiple Plots on One Page, Three-Dimensional Plotting, Plotting
+@section Plot Annotations
+
+@deftypefn {Function File} {} grid
+For two-dimensional plotting, force the display of a grid on the plot.
+@end deftypefn
+
+@deftypefn {Function File} {} title (@var{string})
+Specify a title for the plot.  If you already have a plot displayed, use
+the command @code{replot} to redisplay it with the new title.
+@end deftypefn
+
+@deftypefn {Function File} {} xlabel (@var{string})
+@deftypefnx {Function File} {} ylabel (@var{string})
+@deftypefnx {Function File} {} zlabel (@var{string})
+Specify x, y, and z axis labels for the plot.  If you already have a plot
+displayed, use the command @code{replot} to redisplay it with the new
+labels.
+@end deftypefn
+
+@node Multiple Plots on One Page,  , Plot Annotations, Plotting
+@section Multiple Plots on One Page
+
+The following functions all require a version of @code{gnuplot} that
+supports the multiplot feature.
+
+@deftypefn {Function File} {} mplot (@var{x}, @var{y})
+@deftypefnx {Function File} {} mplot (@var{x}, @var{y}, @var{fmt})
+@deftypefnx {Function File} {} mplot (@var{x1}, @var{y1}, @var{x2}, @var{y2})
+This is a modified version of the @code{plot} function that works with
+the multiplot version of @code{gnuplot} to plot multiple plots per page. 
+This plot version automatically advances to the next subplot position
+after each set of arguments are processed.
+
+See the description of the @var{plot} function for the various options.
+@end deftypefn
+
+@deftypefn {Function File} {} multiplot (@var{xn}, @var{yn})
+Sets and resets multiplot mode.
+
+If the arguments are non-zero, @code{multiplot} will set up multiplot
+mode with @var{xn}, @var{yn} subplots along the @var{x} and @var{y}
+axes.  If both arguments are zero, @code{multiplot} closes multiplot
+mode.
+@end deftypefn
+
+@deftypefn {Function File} {} oneplot ()
+If in multiplot mode, switches to single plot mode.
+@end deftypefn
+
+@deftypefn {Function File} {} plot_border (...)
+Multiple arguments allowed to specify the sides on which the border
+is shown.  Allowed arguments include:
+
+@table @code
+@item "blank"
+No borders displayed.
+
+@item "all"
+All borders displayed
+
+@item "north"
+North Border
+
+@item "south"
+South Border
+
+@item "east"
+East Border
+
+@item "west"
+West Border
+@end table
+
+@noindent
+The arguments may be abbreviated to single characters.  Without any
+arguments, @code{plot_border} turns borders off.
+@end deftypefn
+
+@deftypefn {Function File} {} subplot (@var{rows}, @var{cols}, @var{index})
+@deftypefnx {Function File} {} subplot (@var{rcn})
+Sets @code{gnuplot} in multiplot mode and plots in location
+given by index (there are @var{cols} by @var{rows} subwindows).
+
+Input:
+
+@table @var
+@item rows
+Number of rows in subplot grid.
+
+@item columns
+Number of columns in subplot grid.
+
+@item index
+Index of subplot where to make the next plot.
+@end table
+
+If only one argument is supplied, then it must be a three digit value
+specifying the location in digits 1 (rows) and 2 (columns) and the plot
+index in digit 3.
+
+The plot index runs row-wise.  First all the columns in a row are filled
+and then the next row is filled.
+
+For example, a plot with 4 by 2 grid will have plot indices running as
+follows:
+@iftex
+@tex
+\vskip 10pt
+\hfil\vbox{\offinterlineskip\hrule
+\halign{\vrule#&&\qquad\hfil#\hfil\qquad\vrule\cr
+height13pt&1&2&3&4\cr height12pt&&&&\cr\noalign{\hrule}
+height13pt&5&6&7&8\cr height12pt&&&&\cr\noalign{\hrule}}}
+\hfil
+\vskip 10pt
+@end tex
+@end iftex
+@ifinfo
+@display
+@group
++-----+-----+-----+-----+
+|  1  |  2  |  3  |  4  |
++-----+-----+-----+-----+
+|  5  |  6  |  7  |  8  |
++-----+-----+-----+-----+
+@end group
+@end display
+@end ifinfo
+@end deftypefn
+
+@deftypefn {Function File} {} subwindow (@var{xn}, @var{yn})
+Sets the subwindow position in multiplot mode for the next plot.  The
+multiplot mode has to be previously initialized using the
+@code{multiplot} function, otherwise this command just becomes an alias
+to @code{multiplot}
+@end deftypefn
+
+@deftypefn {Function File} {} top_title (@var{string})
+@deftypefnx {Function File} {} bottom_title (@var{string})
+Makes a title with text @var{string} at the top (bottom) of the plot.
+@end deftypefn