function Ky = getky(K,y,m,n)
MN = repmat([m],[1 n]);
Ky = [];
mn = m^n;
for ind = 1:mn
  z = ind2coord(ind,MN);
  if z(end)==y
    Ky(end+1) = K(ind);
  end
end
Ky = reshape(Ky,size(K(1:length(Ky))));
return