function kvfgui(action)
% KVFGUI
%
% kvfgui(data) öppnar ett fönster för demonstration av kovarianser.
% Data är en vektor med observationer som skall undersökas.
%
% Markera tau-värden i kovariansfunktionsbilden.
% Markera datareferenspunkt i databilden.
% Markerad referenspunkt visas som lodrätt streck (rött), och
% jämförelsepunkterna visas som röda cirklar.
% Kovariansen beräknad med de urvalda punkterna visas med en
% röd ring i kovariansbilden.
% Bilden i det övre högra hörnet visar en scatterplot över den
% valda punktsekvensen.

% Copyright Finn Lindgren 2000-01-16
%                         2000-01-21 Improved "red line" height.

if nargin<1
  action='init';
  thedata=randn(1,100);
elseif ~ischar(action)
  thedata=action;
  action='init';
end

switch action
  case 'init',
    initkvf;
    f=gcf;
    set(f,'Renderer','painters')
    data.db=set_doublebuffer(f);
    
    data.h_data=findobj(f,'Tag','axes_data');
    data.h_kvf=findobj(f,'Tag','axes_kvf');
    data.h_scatter=findobj(f,'Tag','axes_scatter');

    data.h_kvf_max_tau=findobj(f,'Tag','kvf_max_tau');
    data.kvf_max_tau=100;
    set(data.h_kvf_max_tau,'String',[10 20 50 100 200 500 1000],'Value',4);

    data.h_tau=findobj(f,'Tag','tau');
    data.tau=1;
    set(data.h_tau,'String',int2str(data.tau));

    data.t=1:length(thedata);
    data.data=thedata;
    data.h_data_data=line(data.t,data.data,'Parent',data.h_data,...
            'ButtonDownFcn','kvfgui(''mark'')');
    
    data.mark=1;
    data.data_mark_limits = calc_data_mark_limits(data.data);
    data.h_data_mark=line([data.t(data.mark),data.t(data.mark)],...
			  data.data_mark_limits,...
			  'LineStyle','-','Color',[1 0 0],...
			  'ButtonDownFcn','kvfgui(''mark'')',...
			  'Parent',data.h_data);
    
    data.h_kvf_mark=line(0,0,...
      'LineStyle','none','Marker','o','Color',[1 0 0],...
      'ButtonDownFcn','kvfgui(''kvf_tau'')',...
      'Parent',data.h_kvf);
    
    data.index = mod(data.mark-1,data.tau)+1:data.tau:length(data.data);
    data.h_data_marks=line(data.t(data.index),data.data(data.index),...
      'LineStyle','none','Marker','o','Color',[1 0 0],...
      'ButtonDownFcn','kvfgui(''mark'')',...
      'Parent',data.h_data);
   
    data.kvf_tau=0:data.kvf_max_tau;
    data.kvf_data=calccov(data.data,data.kvf_max_tau);
    data.h_kvf_data=line(data.kvf_tau,data.kvf_data,'Parent',data.h_kvf,...
            'ButtonDownFcn','kvfgui(''kvf_tau'')');
    
    data.scatter{1}=data.data(data.index(1:end-1));
    data.scatter{2}=data.data(data.index(2:end));
    data.h_scatter_data=line(data.scatter{1},data.scatter{2},...
      'LineStyle','none','Marker','o','Color',[1 0 0],...
      'Parent',data.h_scatter);
    
    data.h_data_width=findobj(f,'Tag','data_width');
    data.data_width=length(data.data);
    w=makedatawidth(data.data_width);
    set(data.h_data_width,'String',w,'Value',length(w));
    
    data.h_data_start=findobj(f,'Tag','data_start');
    data.data_start=1;
    set(data.h_data_start,'String',makedatastart(length(data.data),w(end)));

    set(f,'UserData',data);
    set(f,'HandleVisibility','callback');
    
    updatekvfmark(f);
    updatedataaxis(f);
  case 'kvf_max_tau',
    f=gcbf;
    data=get(f,'UserData');
    s=get(data.h_kvf_max_tau,'String');
    data.kvf_max_tau=sscanf(s(get(data.h_kvf_max_tau,'Value'),:),'%i');
    set(f,'UserData',data);
    updatekvf(f);
  case 'mark',
    f=gcbf;
    data=get(f,'UserData');
    p=get(data.h_data,'CurrentPoint');
    data.mark=max(1,min(length(data.data),round(p(1,1))));
    set(f,'UserData',data);
    updatedatamark(f);
    updatedatamarks(f);
    updatescatter(f);
    updatekvfmark(f);
  case 'tau',
    f=gcbf;
    data=get(f,'UserData');
    data.tau=limittau(round(sscanf(get(data.h_tau,'String'),'%i')),length(data.data));
    set(data.h_tau,'String',int2str(data.tau));
    set(f,'UserData',data);
    updatedatamark(f);
    updatedatamarks(f);
    updatescatter(f);
    updatekvfmark(f);
  case 'kvf_tau',
    f=gcbf;
    data=get(f,'UserData');
    p=get(data.h_kvf,'CurrentPoint');
    data.tau=limittau(round(p(1,1)),length(data.data));
    set(data.h_tau,'String',int2str(data.tau));
    set(f,'UserData',data);
    updatedatamark(f);
    updatedatamarks(f);
    updatescatter(f);
    updatekvfmark(f);
  case 'data_start',
    f=gcbf;
    data=get(f,'UserData');
    s=get(data.h_data_start,'String');
    data.data_start=sscanf(s(get(data.h_data_start,'Value'),:),'%i');
    set(f,'UserData',data);
    updatedataaxis(f);
    updatedatamark(f);
  case 'data_width',
    f=gcbf;
    data=get(f,'UserData');
    s=get(data.h_data_width,'String');
    data.data_width=sscanf(s(get(data.h_data_width,'Value'),:),'%i');
    set(f,'UserData',data);
    updatedatastart(f,data.data_start,data.data_width);
    updatedataaxis(f);
    updatedatamark(f);
  otherwise,
    disp(['Unknown action: ' action])
end


function t=limittau(t0,l)
t=max(1,min(floor(l/2),t0));


function updatekvf(f)
data=get(f,'UserData');
data.kvf_tau=0:data.kvf_max_tau;
data.kvf=calccov(data.data,data.kvf_max_tau);
set(data.h_kvf_data,'XData',data.kvf_tau,'YData',data.kvf);
set(f,'UserData',data);

function updatescatter(f)
data=get(f,'UserData');
data.scatter{1}=data.data(data.index(1:end-1));
data.scatter{2}=data.data(data.index(2:end));
set(data.h_scatter_data,'XData',data.scatter{1},'YData',data.scatter{2});
set(f,'UserData',data);

function updatedatamark(f)
data=get(f,'UserData');
set(data.h_data_mark,...
    'XData',[data.t(data.mark),data.t(data.mark)],...
    'YData',data.data_mark_limits);
set(f,'UserData',data);

function lim = calc_data_mark_limits(x)
m=max(-min(x),max(x));
e=floor(log(m)/log(10));
m=m*10^(-e);
m=ceil(m);
m=m*10^(e);
lim=[-m,m];


function updatekvfmark(f)
data=get(f,'UserData');
m=mean(data.data);
set(data.h_kvf_mark,'XData',data.t(data.tau),'YData',...
  sum((data.data(data.index(1:end-1))-m).*(data.data(data.index(2:end))-m))/...
  length(data.index));
set(f,'UserData',data);

function updatedatamarks(f)
data=get(f,'UserData');
data.index = mod(data.mark-1,data.tau)+1:data.tau:length(data.data);
set(data.h_data_marks,'XData',data.t(data.index),'YData',data.data(data.index));
set(f,'UserData',data);



function updatedataaxis(f)
data=get(f,'UserData');
set(data.h_data,...
    'XLim',[data.data_start,data.data_start+data.data_width],...
    'YLim',data.data_mark_limits);
set(f,'UserData',data);


function updatedatastart(f,start,width)
data=get(f,'UserData');
s=makedatastart(length(data.data),width);
i=max(1,sum((s<start)));
set(data.h_data_start,'String',s,'Value',i);
data.data_start=s(i);
set(f,'UserData',data);

function i=makedatastart(l,w)
i=1:floor(w/2):l-w+1;
if ~(i(end)==l-w+1)
  i=[i,l-w+1];
end

function i=makedatawidth(l)
idx=[1 2 5]*10;
i=idx;
while (1+i(end)<=l)
  idx=idx*10;
  i=[i,idx];
end
i(1+i>l)=[];
if ~(i(end)==l)
  i=[i,l];
end

function kvf=calccov(data,max_tau)

kvf=conv(data(:)'-mean(data),fliplr(data(:)')-mean(data));
kvf=kvf(end-length(data)+1:end);
if (max_tau>length(kvf)-1)
  kvf=[kvf zeros(1,max_tau-length(kvf)+1)];
elseif (max_tau<length(kvf)-1)
  kvf(max_tau+2:end)=[];
end
kvf = kvf/length(data);


function ok=set_doublebuffer(f)

v=version;
i=[0,sort([findstr(v,'.'),findstr(v,' ')]),length(v)+1];
for k=1:length(i)-1
  vv{k}=v(i(k)+1:i(k+1)-1);
end
if (num2str(vv{1})>5) | ((num2str(v{1})==5) & (num2str(v{2})>=2))
  set(f,'doublebuffer','on') % Undocumented feature in Matlab5.2!
			     % Documented in Matlab5.3!
  ok=1;
else
  ok=0;
end