In the Analysis Selections dialog you specify which items (in the input data files) the directional analysis should be based on. You specify:
1. The elevation (or water depth) item
2. The velocity (or flux) item in the 1. direction (y-component)
3. The velocity (or flux) item in the 2. direction (x-component)
The “Parameter set” is set to “Basic” for analysis or “None” for disregarding the current setting.