clear all
for n = 1:101
  i1 = round(((n-1)*rand/3+1));
  i2 = round(((n-1)*rand/3+1));
  i3 = round(((n-1)*rand/3+1));
  n = i1+i2+i3;
  T1 = triu(rand(i1))+i*triu(rand(i1));
  X = rand(i1,i2);
  Y = rand(i1,i3);
  O1 = zeros(i2,i1);
  B = rand(i2,i2);
  Z = rand(i2,i3);
  O2 = zeros(i3,i1+i2);
  T2 = triu(rand(i3));
  A = [T1 X Y;O1 B Z;O2 T2];
  iperm = randperm(n);
  B = A(iperm,iperm);
%  norm(expm(B)-expmdemo1(B))
  if (norm(expm(B)-expmdemo1(B)) ~= 0)
    n,i1,i2,i3
    A
    B
    break
  end  
end