function graphtest(n0,n1)
global A
global LEVELS
m = 2;
mrat = 0;
for c=1:1e9
  n = round(randinseg(n0,n1));
  T = randdtree(n);
  %A = randtreeA(T,m);
  %C = pnormdim(rand(m,1),1);
  %P = dtreefillprob1(m,n,T,A,C);
  %[hh,Ht,H] = gethhn(P,m,n);
  %r = submulthh(T,hh);
  %mrat = max(mrat,r);
  L = treewidth(T);
  for i=1:n-1
    %Ei = getEi(T,i);
    %nE = size(Ei,1);
    %if nE>2*w-1
    %  'bad E bound'
    %  keyboard
    %end
    for j=i+1:n
      dp = dpath(T,i,j);
      h = length(dp)-1;
      tha = rand;
      if ~isempty(dp)
        lhs = (1-(1-tha)^L)^floor((j-i)/L);
        %rhs = ((1-(1-tha)^L)^(1/(2*L-1)))^(j-i);
        rhs = ((1-(1-tha)^L)^(1/(2*L)))^(j-i);
        if lhs > rhs
          'bad dp bound'
          keyboard
        end
      end
    end
  end
  %fprintf('mrat = %1.10f;     n=%d   checked %d \n',mrat,n,c);
  fprintf('n=%d   checked %d \n',n,c);
end
return

function [ell0,LEVu] = getLevu(u)
global LEVELS
for ell=1:length(LEVELS)
  if ismember(u,LEVELS{ell})
    LEVu = LEVELS{ell};
    ell0 = ell;
    return
  end
end
return


function graphtest0(n)
global minT maxT minu maxu

minr = Inf;
maxr = -Inf;

while 1
  T = randdtree(n);
  d = fanout(T);
  
  for u=1:n
    el0 = reallevel(T,u);
    el1 = lambda(u,d);
    
    r = el1/(el0+realmin);
    if r < minr
      minT=T; minu = u;
      minr = r;
    end
    if r > maxr
      maxT=T; maxu = u;
      maxr = r;
    end
    fprintf('n=%d    minr = %1.5f     maxr = %1.5f   \n',n,minr,maxr);
  end
end

return


function el = reallevel(T,u)
v = u;
el = 0;
while v~=1
  el = el+1;
  rents = find(T(:,v));
  if length(rents)~=1
    'bad tree'
    keyboard
  end
  v = rents;
  
  if el > size(T,1)
    'runaway loop'
    keyboard
  end
end
return

function el = lambda(u,d)
if d==1
  el = u-1;
else
  el = floor(log(u*(d-1)+1)/log(d))-1;
  %el1 = floor(log(u)/log(d))-1;
  %el1 = pl(el1);
  el1 = floor(log(pl(u-1))/log(d));
  %if (el0~=el)
  good = el1 <= el;
  %good = el1>-1;
  if ~good
    'hm'
    keyboard
  end
end
return