Nesting 3D fields

[BillyBoy996]

Question

Question

Hi, I am having trouble nesting two 3D velocity fields in Parcels. I am loading both in from MITgcm outputs. When it comes to creating a fieldset from 3 dimensions from two separate fields I just get error messages because it doesn't recognise inputting the 3 velocity fields into the fieldset. Do I have to add the W velocity field later?

Supporting code/error messages

variables = {
    "U": "UVEL",
    "V": "VVEL",
    "W": "WVEL",
}
mesh_mask = grid_file #ensure mesh mask is the file path not the data

gr_h = xr.open_dataset(high_grid)
variables_h = {
    "U_h": "UVEL",
    "V_h": "VVEL",
    "W_h": "WVEL",
}
high_mask = high_grid #ensure mesh mask is the file path not the data
filenames = {
    "U": {"lon": mesh_mask, "lat": mesh_mask, "depth": mesh_mask, "data": ufiles},
    "V": {"lon": mesh_mask, "lat": mesh_mask, "depth": mesh_mask, "data": ufiles},
    "W": {"lon": mesh_mask, "lat": mesh_mask, "depth": mesh_mask, "data": ufiles},
}
c_grid_dimensions = {
    "lon": "XG",
    "lat": "YG",
    "depth": "Zl",
    "time": "time",
}
dimensions = {"U": c_grid_dimensions, "V": c_grid_dimensions, "W": c_grid_dimensions}

fieldset_coarse = parcels.FieldSet.from_mitgcm(filenames, variables, dimensions, allow_time_extrapolation=True)

hr_files = sorted(glob(f"{high_dir}/hiRGEMS_{year}.nc"))
filenames_h = {
    "U_h": {"lon": high_mask, "lat": high_mask, "depth": high_mask, "data": hr_files},
    "V_h": {"lon": high_mask, "lat": high_mask, "depth": high_mask, "data": hr_files},
    "W_h": {"lon": high_mask, "lat": high_mask, "depth": high_mask, "data": hr_files},
}
c_grid_dimensions_h = {
    "lon": "XG",
    "lat": "YG",
    "depth": "Zl",
    "time": "time",
}

dimensions_h = {"U_h": c_grid_dimensions_h, "V_h": c_grid_dimensions_h, "W_h": c_grid_dimensions_h}
fieldset_hr = parcels.FieldSet.from_mitgcm(filenames_h, variables_h, dimensions_h, allow_time_extrapolation=True)

U = parcels.NestedField("U", [fieldset_hr.U_h, fieldset_coarse.U])
V = parcels.NestedField("V", [fieldset_hr.V_h, fieldset_coarse.V])
W = parcels.NestedField("W", [fieldset_hr.W_h, fieldset_coarse.W])

# create combined fieldset
fieldset = parcels.FieldSet(U, V)
fieldset.add_field(W)

# Paste your error message within this block

[erikvansebille]

Hi @BillyBoy996, what is the error message you get? Please paste the entire error message