how do i execute file under radio button only when i press start button

i have 3 radio buttons with 3 different files i want to select one of them without executing that file, then when i press start button iwant that file to execute.

Answer 1

[Image Analyst]

In the callback for the "Start" push button:

if get(handles.radioButton1, 'Value')
  % Run function #1
  function1;
elseif get(handles.radioButton2, 'Value')
  % Run function #2
  function2;
else
  % Run function #3
  function3;
end

You don't need anything in the callback of the radiobuttons or their group.