function zoompls(action)
%ZOOMPLS GUI for zooming in plots
%  Places a graphical user interface for zooming in
%  2D plots on an existing figure.
%
%  Note that the function attaches the gui to the lower
%  right hand corner of the figure window and is not
%  resized when the plot is resized.
%
%I/O format: zoompls

%Copyright Eigenvector Research 1996-97
%nbg 5/17/97,6/97

if nargin<1
  bgc0       = [0 0 0];
  bgc1       = [1 0 1]*0.6;
  bgc2       = [1 1 1]*0.85;
  a          = gcf;
  if isempty(findobj('Tag',['ZoomFrame',int2str(a)]));
    s        = get(a,'ResizeFcn');
    s1       = 'zoompls(''ZOOMPLSsize'');';
    set(a,'ResizeFcn',[s,s1]);
    p(1,1:4) = get(a,'position');
    p(1,1)   = p(1,3)-74;
    p(1,2)   = 3;
    p(1,3:4) = [0 0];
    b        = zeros(6,5);
    b(1,2:5) = [ 0  0 74 56+14];
    b(2,2:5) = [ 2  2 34 25];
    b(3,2:5) = [ 2 29 34 25];
    b(4,2:5) = [38 29 34 25];
    b(5,2:5) = [ 2 56 70 14];
    b(6,2:5) = [38  2 34 25];
    x        = axis;
    s        = ['ZoomFrame',int2str(a)];
 
    b(1,1) = uicontrol('Parent',a, ...
	   'BackgroundColor',bgc1,'Tag',s, ...
	   'Style','Frame','position',p+b(1,2:5));
    b(2,1) = uicontrol('Parent',a, ...
	   'CallBack','zoompls(''viewdefault'')', ...
	   'String','home','UserData',x);
    b(3,1) = uicontrol('Parent',a, ...
	   'CallBack','zoompls(''into'')',	...
	   'String','in', ...
	   'Tag','PushOrbit2');
    b(4,1) = uicontrol('Parent',a, ...
	   'CallBack','zoompls(''outof'')', ...
	   'String','out');
    b(5,1) = uicontrol('Parent',a, ...
     'Style','Text', ...
	   'FontWeight','bold','ForegroundColor',[1 1 1], ...
	   'String','zoom','HorizontalAlignment','center');
    b(6,1) = uicontrol('Parent',a, ...
	   'CallBack','zoompls(''exitzoom'')', ...
	   'String','quit');

    for jj=2:6
      set(b(jj,1),'position',p+b(jj,2:5), ...
	    'BackgroundColor',bgc2,'Interruptible','off', ...
	    'BusyAction','cancel', ...
	    'FontName','Geneva','Fontsize',9)
    end
    set(b(5,1),'BackgroundColor',bgc1)
    set(b(1,1),'UserData',b)
  end
else
  s      = ['ZoomFrame',int2str(gcf)];
  b      = get(findobj('Tag',s),'UserData');
  if ~isempty(b)
    x    = get(b(2,1),'UserData');
    if strcmp(action,'viewdefault')
      x  = x(1,:);
	    axis(x)
    elseif strcmp(action,'ZOOMPLSsize')
      p(1,1:4) = get(gcf,'position');
      p(1,1)   = p(1,3)-74;
      p(1,2)   = 3;
      p(1,3:4) = [0 0];
      for jj=1:6
        set(b(jj,1),'position',p+b(jj,2:5))
      end
    elseif strcmp(action,'into')
      set(b(:,1),'Visible','Off')
      v(1:2,1) = ginput(1)';
	    v(1:2,2) = ginput(1)';
	    if v(1,2)<v(1,1)
	      m      = v(1,2);
	      v(1,2) = v(1,1);
	      v(1,1) = m;
	    end
	    if v(2,2)<v(2,1)
	      m      = v(2,2);
	      v(2,2) = v(2,1);
	      v(2,1) = m;
	    end
	    v        = [v(1,:), v(2,:)];
	    axis(v)
	    x        = [x;v];
    elseif strcmp(action,'outof')
      m       = size(x,1);
	    if m>1
	      x     = x(1:m-1,:);
	      axis(x(m-1,:))
	    else
	      x     = x(1,:);
	      axis(x)
	    end
    end
    if strcmp(action,'exitzoom')
      for i1=1:6
        delete(b(i1,1))
      end
    else
      set(b(2,1),'UserData',x)
      set(b(:,1),'Visible','On')
    end
  end
end