wolffd@0: function pot = combine_pots(pot1, pot2)
wolffd@0: % COMBINE_POTS combine two potentials 
wolffd@0: % pot = combine_pots(pot1, pot2)
wolffd@0: 
wolffd@0: % Reduce both potentials before trying to combine them. 
wolffd@0: % Cf. "Stable Local computation with Conditional Gaussian Distributions", page 9
wolffd@0: % Consider again two potentials with minimal tail
wolffd@0: 
wolffd@0: % Guarantee minimal tails. If pot1 or pot2 are minimal, they are not changed
wolffd@0: pot1 = reduce_pot(pot1);
wolffd@0: pot2 = reduce_pot(pot2);
wolffd@0: 
wolffd@0: %if the intersect set of these two potentials' head conts. combination is undifined
wolffd@0: if ~isempty( myintersect(pot1.cheaddom, pot2.cheaddom) )
wolffd@0:     return;
wolffd@0: end
wolffd@0: 
wolffd@0: if  isempty( myintersect(pot1.domain, pot2.cheaddom) ) | isempty( myintersect(pot2.domain, pot1.cheaddom))
wolffd@0:     % if satisfy the condition of directed combine
wolffd@0:     pot = direct_combine_pots(pot1, pot2);
wolffd@0: else
wolffd@0:     % perform recursive combine
wolffd@0:     pot = recursive_combine_pots(pot1, pot2);
wolffd@0: end