Hello Martin, > This is a nice example, but I wonder: using a mask in this case means applying > the contraints in a "all or nothing" fashion. This is quite convenient for > exploratory work. But as the model become more elaborate, I would intuitively > (I > may be totally wrong - I work more with oceans than habitats) expect the "all > or > nothing" behavior to be replaced by some sigmoid function
Yes - I think you are right. I have used various forms of sigmoid functions, esp. inverse logistic, in other ecological models. In my present project the model is directed towards species that establish and defend territories, so the crude representation of a bounded, exclusive area is (possibly) not unreasonable - even though in the real world adjacent territory boundaries are fuzzy and resource availability there would be better modelled by a sigmoid function. But then modelling is mostly about the trade-off between complexity and detail of representation on the one hand against tractability, testability and being able to actually parameterize the model on the other hand. I imagine this is also the case in oceanography. More of an art than a science :-) > I don't have a clear opinion on this topic since I believe that it depends on > the experience gained with pratical work, and this experience is likely to > vary > in different applications. The rules approach is nice if the rules can be > simple > and "universal" enough, otherwise controlling images are preferable. But my > notion of "universal" is biased toward what I have seen in oceanography > (continuous functions are more frequent than discontinuities, hence my > preference for a sigmoid function in my previous paragraph), and my position > sometime change with time... So I can not really emmit a reliable advice here. Would it be possible / useful to add new operators to a new or existing unsupported module ? I need to do more such work for my project anyway, and if I could add them to the geotools unsupported modules it would be very helpful for me to get feedback on the operators. Michael ------------------------------------------------------------------------------ Check out the new SourceForge.net Marketplace. It is the best place to buy or sell services for just about anything Open Source. http://p.sf.net/sfu/Xq1LFB _______________________________________________ Geotools-gt2-users mailing list Geotools-gt2-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
