MATLAB: How to use guidata to pass 2 different variables in 2 different callbacks of a GUI

Question

My GUI is required to-

Browse for .mat and .wav files. Store the file names in storedStructure and storedStructure1.

Use load and wavread in seperate callbacks and plot those 2 functions.

Upon loading the .wav file, I plotted it without any problems. But there are problems with the .mat file.

Here's my code:

startingFolder = 'C:\Users\Mayank\Desktop\Matlab';
% Get the name of the mat file that the user wants to use.
defaultFileName = fullfile(startingFolder, '*.mat');
[baseFileName, folder] = uigetfile(defaultFileName, 'Select a mat file');
if baseFileName == 0
  % User clicked the Cancel button.
  return;
end
fullFileName = fullfile(folder, baseFileName);
storedStructur = fullFileName;
handles.b = storedStructur;
guidata(hObject,handles);
axes(handles.Sensor);
ema = load(handles.b);
plot(ema);

The error being-

Error using plot
Not enough input arguments.
Error in Speech_Proc>pushbutton10_Callback (line 149)
plot(ema);
Error in gui_mainfcn (line 96)
        feval(varargin{:});
Error in Speech_Proc (line 42)
    gui_mainfcn(gui_State, varargin{:});
Error in
@(hObject,eventdata)Speech_Proc('pushbutton10_Callback',hObject,eventdata,guidata(hObject))
Error while evaluating uicontrol Callback

Answer 1

When you load() a .mat file, the result is a structure with fields named after the variables stored in the file. When you plot() you need to specify which field to plot. For example if what was stored in the .mat file was a variable named "sound_data", then you would

plot(ema.sound_data);