interactivelegend

 INTERACTIVELEGEND    Makes a figure interactive
   This function make plots in a figure act in an interactive way: when
   selected, they are highlighted and an associated tag is shown. Clicking
   on the axes background unselects the plot. This can be used to avoid
   the use of a cumbersome legend when a figure contains many plots.

   Syntaxes:

       interactivelegend(handles);
       interactivelegend(handles,opts);

   These syntaxes enable interactivity for the plots whose handles are given
   in vector "handles", and displays their 'Tag' property (which are empty
   strings by default). Details of how the plots are highlighted are given
   in the (optional) structure "opts". See below for a description of the
   option structure "opts".

   Vector "handles" can also contain handles to axes: interactivelegend 
   then automatically finds the axes' children and all the plot objects
   in these axes will be interactive. Thus, the function can be simply
   called for the current figure with the command "gca" in lieu of vector
   "handles":
   
       interactivelegend(gca)

   will actually work.

   Syntaxes:

       interactivelegend(handles,tags);
       interactivelegend(handles,tags,opts);

   These syntaxes first assign the tags in cell array "tags" to the plots'
   'Tag' properties, and displays them when they are highlighted as
   before.

   The optional structure "opts" is used to adjust various properties of
   the interactive objects. Note that field names are case sensitive.

       opts.selected.Color         is the plot's highlighted color
       opts.selected.LineStyle     is the plot's highlighted linestyle
       opts.selected.LineWidth     is the plot's highlighted linewidth
       ...                         

   In general, any plot object property can be adjusted using the field
   opts.selected.PROPERTY. 

       opts.unselected             is a structure describing the
                                   unselected plots properties.

   By default, opts.unselected is simply the original property structure,
   so that opts.unselected needs not be specified. If specified, the
   properties in opts.unselected are applied to the plots when they are
   not selected.

       opts.tag.Color              is the text tag's color
       ...

   In general, any text tag property can be adjusted using the field
   opts.tag.PROPERTY. In particular, opts.tag.Color defaults to 
   opts.selected.Color. Note however that opts.tag.String should not be
   specified since it will override the displayed text (and will be the
   same for all tags).

       opts.pointer               is the figure's pointer

   Default is a crosshair; see set(gcf,'Pointer') for all pointer types.

   If structure "opts" is ommitted, the following default values are used:

       opts.selected.Color = 'r';
       opts.selected.LineWidth = 2;
       opts.tag.Color = 'r';
       opts.pointer = 'crosshair';

   Note that "opts" is stored in the 'UserData' fields of all the axes
   containing interactive objects. Any data which is stored in the axes' 
   'UserData' field will be overwritten. Additionnal fields are created
   by interactivelegend in structure "opts" to store the interactive
   objects' states. This means that bad behavior will be obtained if the
   function is called successively after each plot, such as in:

       hold on;
       p1 = plot(...);
       interactivelegend(p1);
       p2 = plot(...);
       interactivelegend(p2);
       etc.

   Each time interactivelegend is called, data from the previous calls is
   erased from the axes 'UserData' field. The correct way to do this would
   be:

       hold on;
       p1 = plot(...);
       p2 = plot(...);
       interactivelegend([p1 p2]);

   or even:

       hold on;
       plot(...);
       plot(...);
       interactivelegend(gca);

   Function interactivelegend should be called at most one time for each
   axes; if the provided handles span many axes, the function will still
   work but the interactive objects will behave as a single set (e.g.
   selected plots in one axes will be deselected if another axes
   containing interactive plots are selected, whereas different axes will
   behave independantly if interactivelegend is called once for each
   axes).