pwGetInfluencedSpecies

 [influenced, notInfluenced] = pwGetInfluencedSpecies(species, modelIndex)

 Determines all species that are influenced by a given species
 in the given model, i.e. which has a non-zero sensitivity on
 the given species based on the model structure.

 If no model is specified,  the highest currently selected model of the
 couple-list is used.