Merge pull request #4 from NOAA-GFDL/fix/break-pyFV3-dependency

[fix] Break pyFV3 dependency

ndsl/dsl/dace/wrapped_halo_exchange.py

@@ -1,5 +1,5 @@
 import dataclasses
-from typing import List, Optional
+from typing import Any, List, Optional
 
 from ndsl.comm.communicator import Communicator
 from ndsl.dsl.dace.orchestration import dace_inhibitor
@@ -29,6 +29,14 @@ def __init__(
         self._qtx_y_names = qty_y_names
         self._comm = comm
 
+    @staticmethod
+    def check_for_attribute(state: Any, attr: str):
+        if dataclasses.is_dataclass(state):
+            return state.__getattribute__(attr)
+        elif isinstance(state, dict):
+            return attr in state.keys()
+        return False
+
     @dace_inhibitor
     def start(self):
         if self._qtx_y_names is None:

ndsl/grid/eta.py

@@ -1,10 +1,15 @@
+import math
 import os
 from dataclasses import dataclass
 
 import numpy as np
 import xarray as xr
 
 
+ETA_0 = 0.252
+SURFACE_PRESSURE = 1.0e5  # units of (Pa), from Table VI of DCMIP2016
+
+
 @dataclass
 class HybridPressureCoefficients:
     """
@@ -75,7 +80,23 @@ def set_hybrid_pressure_coefficients(
     return pressure_data
 
 
-def check_eta(ak, bk):
-    from pyFV3.initialization.init_utils import compute_eta
+def vertical_coordinate(eta_value):
+    """
+    Equation (1) JRMS2006
+    computes eta_v, the auxiliary variable vertical coordinate
+    """
+    return (eta_value - ETA_0) * math.pi * 0.5
+
 
+def compute_eta(ak, bk):
+    """
+    Equation (1) JRMS2006
+    eta is the vertical coordinate and eta_v is an auxiliary vertical coordinate
+    """
+    eta = 0.5 * ((ak[:-1] + ak[1:]) / SURFACE_PRESSURE + bk[:-1] + bk[1:])
+    eta_v = vertical_coordinate(eta)
+    return eta, eta_v
+
+
+def check_eta(ak, bk):
     return compute_eta(ak, bk)

ndsl/stencils/c2l_ord.py

@@ -6,7 +6,6 @@
     interval,
     region,
 )
-import pyFV3
 
 import ndsl.dsl.gt4py_utils as utils
 from ndsl.comm.communicator import Communicator
@@ -157,7 +156,7 @@ class CubedToLatLon:
 
     def __init__(
         self,
-        state: pyFV3.DycoreState,
+        state,  # No type hint on purpose to remove dependency on pyFV3
         stencil_factory: StencilFactory,
         quantity_factory: QuantityFactory,
         grid_data: GridData,
@@ -215,8 +214,6 @@ def __init__(
             compute_halos=halos,
         )
 
-        origin = grid_indexing.origin_compute()
-        shape = grid_indexing.max_shape
         if not self.one_rank:
             full_size_xyiz_halo_spec = quantity_factory.get_quantity_halo_spec(
                 dims=[X_DIM, Y_INTERFACE_DIM, Z_DIM],
@@ -228,6 +225,17 @@ def __init__(
                 n_halo=grid_indexing.n_halo,
                 dtype=Float,
             )
+
+            # TODO:
+            # To break the depedency to pyFV3 we allow ourselves to not have a type
+            # hint around state and we check for u and v to make sure we don't
+            # have bad input.
+            # This entire code should be retired when WrappedHaloUpdater is no longer
+            # required.
+            if not WrappedHaloUpdater.check_for_attribute(
+                state, "u"
+            ) and WrappedHaloUpdater.check_for_attribute(state, "v"):
+                raise RuntimeError("Cube To Lat Lon: state given is not readable.")
             self.u__v = WrappedHaloUpdater(
                 comm.get_vector_halo_updater(
                     [full_size_xyiz_halo_spec], [full_size_xiyz_halo_spec]