stemvalue.m

很多matlab的源代码

function stemvalue(action,XLabel,YLabel)
%STEMVALUE Create right-click popup to show stem plot values.
%   STEMVALUE(hStemPlot,XLabel,YLabel) is a function that enhances
%   the display of plots created with the stem command.  When the
%   user right-clicks on the stem or marker of the stem plot, text 
%   will popup at the mouse location giving the x and y values of
%   the stem plot at that point.
%
%   The input variable hStemPlot should be the vector of handles 
%   returned by the stem command.  The variables XLabel and YLabel 
%   are strings used in the text of the popup.  Both the XLabel and 
%   YLabel arguments should be passed as an input or they should both 
%   be left out.  Leaving out the two variables implies the defaults 
%   XLabel = 'x' and YLabel = 'y' will be used.
%
%   For example,
%
%       h = stem(0:5,1:6);
%       xlabel('t (sec)');
%       ylabel('Amplitude');
%       stemvalue(h,'t','Amplitude');
%
%   If the user then right-clicks on the x=2 stem line, a popup box
%   would display:
% 
%       't = 2'
%       'Amplitude = 3'
%
%   See also STEM

% Jordan Rosenthal, 6/30/99


if ~isstr(action)
   hStemPlot = action;
   action = 'Initialize';   
end

switch action
case 'Initialize'
   if nargin == 1
      h.XLabel = 'x = ';
      h.YLabel = 'y = ';
   else
      error(nargchk(3,3,nargin));
      h.XLabel = [XLabel ' = '];
      h.YLabel = [YLabel ' = '];
   end
   
   myPath = which('stemvalue.m');
   MyDir = myPath(1:end-12);
   CallingDir = evalin('caller','pwd');
   if strcmp(MyDir,CallingDir)
      % stemvalue.m in same directory as calling function so is in path

      sCallback = 'stemvalue ShowXY';

   else
      % stemvalue.m not in same directory so it may not be in path when called

      % This is especially true if it is within a private directory.

      sCallback = [ ...
            'cd ' MyDir ';' ...
            'feval(''stemvalue'',''ShowXY'');' ...
            'cd ' CallingDir ';' ];

   end
   
   hCMenu = uicontextmenu('Callback',sCallback);
   hXMenu = uimenu(hCMenu);
   hYMenu = uimenu(hCMenu);
   h.Menus = [hXMenu; hYMenu];
   h.Markers = hStemPlot(1);
   set(hCMenu,'UserData',h);
   
   set(hStemPlot,'uicontextmenu',hCMenu);
   
case 'ShowXY'

   h = get(gcbo,'UserData');
   CurrPt = get(gca,'CurrentPoint');
   [x,y] = deal(CurrPt(1,1),CurrPt(1,2));
   XData = get(h.Markers,'XData');
   YData = get(h.Markers,'YData');
   [m,k] = min(abs(XData-x));
   sx = [ h.XLabel num2str(XData(k)) ];
   sy = [ h.YLabel num2str(YData(k)) ];
   set(h.Menus,{'Label'},{sx; sy});

   
otherwise
   error('Illegal action.');
end