How to display output from edit text gui?

Hello, i have code bellow

function pushbutton2_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton26 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)  
input1=get(handles.edit13,'String');
  input2=get(handles.edit14,'String');
  input3=get(handles.edit15,'String');
  parameter_c=str2num(input1);
  gamma=str2num(input2);
  probability=str2num(input3);

and also i have a code for libsvm

model = cell(numLabels,1);
for k=1:numLabels
    model{k} = svmtrain(double(trainLabel==k), trainData, '-c 1 -g 0.2 -b 1');
end

i want to change the '-c 1 -g 0.2 -b 1' it's something like

model = cell(numLabels,1);
  for k=1:numLabels
      model{k} = svmtrain(double(trainLabel==k), trainData, '-c parameter_c -g gamma -b probability');
  end

but it says ??? Attempt to reference field of non-structure array.

'-c 1 -g 0.2 -b 1' is a string,isn't it? What should i do? thank you

[Matt Kindig]

You intend to use parameter_c, gamma, and probability as variable names, but you are referring to them as literal strings 'parameter_c', 'gamma', and 'probability'. You need to create a string where the values of the variables are substituted in.

Try this line instead:

model{k} = svmtrain(double(trainLabel==k), trainData, sprintf('-c %d -g %f -b %d', parameter_c, gamma, probability) );

[Jan]

@Matt Kindig: I cannot vote for this useful answer, because you have posted it as a comment.