Clarification of Depth Sign Convention for pyHAMS

[caleboxeng]

Hi Developers,

I wanted to clarify the sign convention for the depth that is given to the pyHAMS write_control_function, which I may be mistaken on!

In examples provided in the HAMS repository, there is a comment that for the depth value, "a negative value denotes the infinite depth". The write_control_file function writes in the negative of the depth value to the control file. Therefore If a positive value is given to the write_control_file function, a negative value will be written to the control file and HAMS will run the BEM for infinite depth.

In raft_fowt.py, the depth value given to the function is fowt.depth, which is defined as positive down. Therefore, the current code will call pyHAMS to be run for infinite depth (given a negative depth is written to the control file) for all depths. I've observed this when running BEM cases via RAFT, and seeing no difference in coefficient values for varying depth inputs. I see a difference when I change to depth=-self.depth in the write_control_function.

[dzalkind]

Thanks for catching this! Do the changes to the coefficient values align with your expectations?