Real Time TCP Data Plotting

Hi I'm trying to plot TCP data in real time and I've modified example code I found here on mathworks. The problem is when I run the example code (and a version I modified) it doesn't update the graph although I can tell it is streaming data. Anyone have a idea why the graph isn't updating? Here is the code I'm working with (with my own minor changes):

%Orginal Code Author Ankit Desai
%Copyright 2010 - The MathWorks, Inc.

 function real_time_data_stream_plotting
    interfaceObject = tcpip('18.111.48.184',23);

    figureHandle = figure('NumberTitle','off',...
    'Name','Live Data Stream Plot',...
    'Color',[0 0 0],...
    'CloseRequestFcn',{@localCloseFigure,interfaceObject});

     axesHandle = axes('Parent',figureHandle,...
                'YGrid','on',...
                'YColor',[0.9725 0.9725 0.9725],...
                'XGrid','on',...
                'XColor',[0.9725 0.9725 0.9725],...
                'Color',[0 0 0]);

     xlabel(axesHandle,'Number of Samples');
     ylabel(axesHandle,'Value');
     ylim([0 4096]);

     %Initialize the plot and hold the settings on
     hold on;
     plotHandle = plot(axesHandle,0,'-y','LineWidth',1);
     bytesToRead = 31;

     %Define a callback function to be executed when desired number of
     %bytes are availabe in the input buffer
     interfaceObject.BytesAvailableFcn ={@localReadAndPlot,plotHandle,bytesToRead};
     interfaceObject.BytesAvailableFcnMode = 'byte';
     interfaceObject.BytesAvailableFcnCount = bytesToRead;
      %Open the interface Object
      fopen(interfaceObject);
      pause(3);
      snapnow;

   %Implement the bytes available CallBack
 function localReadAndPlot(interfaceObject,~,figureHandle,bytesToRead)
       % Read the desired number of data bytes
       data = fread(interfaceObject,bytesToRead);
       dataStr = char(data(1:end-2)')   
        % remove the /n /r characters and convert it to a string
       dataNum = sscanf(dataStr,'%d,%d,%d,%d,%d,%d');   
        % convert the string into numbers
       % Update the plot
       set(figureHandle,'Ydata',dataNum(1)) 

 %Implement the close figure callback
 function localCloseFigure(figureHandle,~interfaceObject)
     fclose(interfaceObject);
     delete(interfaceObject);
     clear interfaceObject;
     delete(figureHandle)

EDIT: I managed to get it to plot the data real time by changing the dataNum(1) to dataNum.

Answer 1

[Matthew Mellor]

Figured it out... Had to change dataNum(1) to dataNum in localReadAndPlot No helped needed :)