How to pass graphic object handle to a function?

hi everyone, i'm using this function:

function [ax,hlines] = plotyyy(x1,y1,x2,y2,x3,y3,ylabels)
%PLOTYYY - Extends plotyy to include a third y-axis
%
%Syntax:  [ax,hlines] = plotyyy(x1,y1,x2,y2,x3,y3,ylabels)
%
%Inputs: x1,y1 are the xdata and ydata for the first axes' line
%        x2,y2 are the xdata and ydata for the second axes' line
%        x3,y3 are the xdata and ydata for the third axes' line
%        ylabels is a 3x1 cell array containing the ylabel strings
%
%Outputs: ax -     3x1 double array containing the axes' handles
%         hlines - 3x1 double array containing the lines' handles
%
%Example:
%x=0:10; 
%y1=x;  y2=x.^2;   y3=x.^3;
%ylabels{1}='First y-label';
%ylabels{2}='Second y-label';
%ylabels{3}='Third y-label';
%[ax,hlines] = plotyyy(x,y1,x,y2,x,y3,ylabels);
%legend(hlines, 'y = x','y = x^2','y = x^3',2)
%
%m-files required: none
%Author: Denis Gilbert, Ph.D., physical oceanography
%Maurice Lamontagne Institute
%Dept. of Fisheries and Oceans Canada
%email: [e-mail]  
%Web: http://www.qc.dfo-mpo.gc.ca/iml/
%April 2000; Last revision: 14-Nov-2001
if nargin==6
   %Use empty strings for the ylabels
   ylabels{1}=' '; ylabels{2}=' '; ylabels{3}=' ';
elseif nargin > 7
   error('Too many input arguments')
elseif nargin < 6
   error('Not enough input arguments')
end
figure('units','normalized',...
       'DefaultAxesXMinorTick','on','DefaultAxesYminorTick','on'); 
%Plot the first two lines with plotyy
[ax,hlines(1),hlines(2)] = plotyy(x1,y1,x2,y2);
cfig = get(gcf,'color');
pos = [0.1  0.1  0.7  0.8];
offset = pos(3)/5.5;
%Reduce width of the two axes generated by plotyy 
pos(3) = pos(3) - offset/2;
set(ax,'position',pos);  
%Determine the position of the third axes
pos3=[pos(1) pos(2) pos(3)+offset pos(4)];
%Determine the proper x-limits for the third axes
limx1=get(ax(1),'xlim');
limx3=[limx1(1)   limx1(1) + 1.2*(limx1(2)-limx1(1))];
%Bug fix 14 Nov-2001: the 1.2 scale factor in the line above
%was contributed by Mariano Garcia (BorgWarner Morse TEC Inc)
ax(3)=axes('Position',pos3,'box','off',...
   'Color','none','XColor','k','YColor','r',...   
   'xtick',[],'xlim',limx3,'yaxislocation','right');
hlines(3) = line(x3,y3,'Color','r','Parent',ax(3));
limy3=get(ax(3),'YLim');
%Hide unwanted portion of the x-axis line that lies
%between the end of the second and third axes
line([limx1(2) limx3(2)],[limy3(1) limy3(1)],...
   'Color',cfig,'Parent',ax(3),'Clipping','off');
axes(ax(2))
%Label all three y-axes
set(get(ax(1),'ylabel'),'string',ylabels{1})
set(get(ax(2),'ylabel'),'string',ylabels{2})
set(get(ax(3),'ylabel'),'string',ylabels{3})

This function plot data in a figure. I need to plot into an axes in GUI, instead of figure. My idea was to add an additional argument to this function, that contains the handle of my "axes" and replace the code (inside the function) about figure with the code of my axes, but i'm new in matlab and i don't know how to do it well.

At the end it should be something like that:

x1 = ....
...
...
y3 = ....
ax2 = handles.axes2;
plotyyy(ax2,x1,y1,x2,y2,x3,y3);

Answer 1

[Walter Roberson]

You are encountering the same difficulty here as in your previous question on this topic. You want to plot into one axes but plotyyy inherently requires three axes. The entire implementation of plotyy and plotyyy is based upon using multiple axes, and this would not be easily overcome.

It would make more sense to define a container object such as a uipanel and plot into it, or else to pass in Position instead of axes to get the results to appear at a particular location. Coding it to allow multiple axes to be passed in would certainly be possible, but it does change how you think about what you are doing, as those axes would have to already exist.