Hi Violet
Tra_prof_z is a function which return a value (and not a vector).
On arguments, you could find:
I : the number of the liquid boundary (you probably have only 1 liquid boundary so no specific treatment linked to this value)
IPOIN2 : the global number of point considered on the boundary. It allow you to manage a vertical profile which vary in space (probably not necessary for you at least for the moment)
TIME and LT : For managing a time varying vertical profile
IPLAN: the plan number considered. You have to use it to affect the right value of tracer
ENTET: no interest
IOPT: linked to the option chose in your sterring file. You have to modify the right part according to this value
ITRAC : the tracer number considered. You have to use it to affect the value
This function is called for every point on a liquid boundary, for each plane and for each tracer.
So you just have to make some tests:
- on ITRAC to select if you should return the value of temperature or salinity
- on IPLAN to select le value of each tracer according to the layer
The other options are here for more complex situation
Hope this helps