You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: circularspecGUI.m
    path of file: ./repos/acycle/code/guicode
    
    the code of the file until where you have to start completion: function varargout = circularspecGUI(varargin)
% CIRCULARSPECGUI MATLAB code for circularspecGUI.fig
%      CIRCULARSPECGUI, by itself, creates a new CIRCULARSPECGUI or raises the existing
%      singleton*.
%
%      H = CIRCULARSPECGUI returns the handle to a new CIRCULARSPECGUI or the handle to
%      the existing singleton*.
%
%      CIRCULARSPECGUI('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in CIRCUL
    
function radiobutton4_Callback(hObject, eventdata, handles)
% hObject    handle to radiobutton4 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hint: get(hObject,'Value') returns toggle state of radiobutton4
val = get(handles.radiobutton4,'Value');
if val == 1
    set(handles.radiobutton3, 'Value', 0);
    set(handles.uibuttongroup1, 'visible', 'off');
else
    set(handles.radiobutton3, 'Value', 1);
    set(handles.uibuttongroup1, 'visible', 'on');
end