Improve StencilTest input_data allocation and deallocation

model/atmosphere/advection/tests/advection/stencil_tests/test_apply_horizontal_density_increment.py

@@ -43,7 +43,7 @@ def reference(
         rhodz_ast2 = np.maximum(0.1 * p_rhodz_new, p_rhodz_new) - p_dtime * tmp
         return dict(rhodz_ast2=rhodz_ast2)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid) -> dict:
         p_rhodz_new = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         p_mflx_contra_v = data_alloc.random_field(

model/atmosphere/advection/tests/advection/stencil_tests/test_apply_interpolated_tracer_time_tendency.py

@@ -37,7 +37,7 @@ def reference(
 
         return dict(p_tracer_new=p_tracer_new)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_tracer_now = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         p_grf_tend_tracer = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_apply_vertical_density_increment.py

@@ -47,7 +47,7 @@ def reference(
 
         return dict(rhodz_ast2=rhodz_ast2)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         rhodz_ast = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         p_mflx_contra_v = data_alloc.random_field(

model/atmosphere/advection/tests/advection/stencil_tests/test_average_horizontal_flux_subcycling_2.py

@@ -34,7 +34,7 @@ def reference(
         p_out_e = (z_tracer_mflx_1_dsl + z_tracer_mflx_2_dsl) / float(2)
         return dict(p_out_e=p_out_e)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         z_tracer_mflx_1_dsl = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         z_tracer_mflx_2_dsl = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_average_horizontal_flux_subcycling_3.py

@@ -35,7 +35,7 @@ def reference(
         p_out_e = (z_tracer_mflx_1_dsl + z_tracer_mflx_2_dsl + z_tracer_mflx_3_dsl) / float(3)
         return dict(p_out_e=p_out_e)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         z_tracer_mflx_1_dsl = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         z_tracer_mflx_2_dsl = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_antidiffusive_cell_fluxes_and_min_max.py

@@ -77,7 +77,7 @@ def reference(
             z_tracer_min=z_tracer_min,
         )
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid) -> dict:
         geofac_div = data_alloc.random_field(grid, dims.CellDim, dims.C2EDim)
         p_rhodz_now = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_barycentric_backtrajectory.py

@@ -79,7 +79,7 @@ def reference(
             p_distv_bary_2=p_distv_bary_2,
         )
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid) -> dict:
         p_vn = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         p_vt = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_barycentric_backtrajectory_alt.py

@@ -72,7 +72,7 @@ def reference(
             p_distv_bary_2=p_distv_bary_2,
         )
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid) -> dict:
         p_vn = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         p_vt = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_ffsl_backtrajectory.py

@@ -145,7 +145,7 @@ def reference(
             "p_coords_dreg_v_4_lat_dsl": p_coords_dreg_v_4_lat_dsl,
         }
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid) -> dict:
         p_vn = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         p_vt = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_ffsl_backtrajectory_counterclockwise_indicator.py

@@ -44,7 +44,7 @@ def reference(
 
         return dict(lvn_sys_pos=lvn_sys_pos)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_vn = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         tangent_orientation = data_alloc.random_field(grid, dims.EdgeDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_ffsl_backtrajectory_length_indicator.py

@@ -46,7 +46,7 @@ def reference(
 
         return dict(opt_famask_dsl=opt_famask_dsl)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid) -> dict:
         p_vn = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         p_vt = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_horizontal_tracer_flux_from_cubic_coefficients.py

@@ -34,7 +34,7 @@ def reference(
 
         return dict(p_out_e_hybrid_2=p_out_e_hybrid_2)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid) -> dict:
         p_out_e_hybrid_2 = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         p_mass_flx_e = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_horizontal_tracer_flux_from_linear_coefficients.py

@@ -57,7 +57,7 @@ def reference(
 
         return dict(p_out_e=p_out_e)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         z_lsq_coeff_1 = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         z_lsq_coeff_2 = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_horizontal_tracer_flux_from_linear_coefficients_alt.py

@@ -57,7 +57,7 @@ def reference(
 
         return dict(p_out_e=p_out_e)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         z_lsq_coeff_1 = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         z_lsq_coeff_2 = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_positive_definite_horizontal_multiplicative_flux_factor.py

@@ -53,7 +53,7 @@ def reference(
 
         return dict(r_m=r_m)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid) -> dict:
         geofac_div = data_alloc.random_field(grid, dims.CellDim, dims.C2EDim)
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_ppm4gpu_parabola_coefficients.py

@@ -36,7 +36,7 @@ def reference(
         z_a1 = p_cc - 0.5 * (z_face_up + z_face_low)
         return dict(z_delta_q=z_delta_q, z_a1=z_a1)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         z_face_up = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         z_face_low = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_ppm_all_face_values.py

@@ -49,7 +49,7 @@ def reference(
         p_face[:, 1:] = np.where((k[1:] == elevp1), p_cc[:, :-1], p_face[:, 1:])
         return dict(p_face=p_face)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         p_cellhgt_mc_now = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_ppm_quadratic_face_values.py

@@ -42,7 +42,7 @@ def reference(
         )
         return dict(p_face=p_face)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_face = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_ppm_quartic_face_values.py

@@ -68,7 +68,7 @@ def reference(
         )
         return dict(p_face=p_face)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         p_cellhgt_mc_now = data_alloc.random_field(

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_ppm_slope.py

@@ -64,7 +64,7 @@ def reference(
         z_slope = np.where(k[1:-1] < elev, z_slope_a, z_slope_b)
         return dict(z_slope=z_slope)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         z_slope = data_alloc.zero_field(grid, dims.CellDim, dims.KDim)
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim, extend={dims.KDim: 1})

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_tendency.py

@@ -34,7 +34,7 @@ def reference(
 
         return dict(opt_ddt_tracer_adv=opt_ddt_tracer_adv)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_tracer_now = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         p_tracer_new = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_vertical_parabola_limiter_condition.py

@@ -36,7 +36,7 @@ def reference(
         l_limit = np.where(np.abs(z_delta) < -1 * z_a6i, 1, 0)
         return dict(l_limit=l_limit)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         p_face = data_alloc.random_field(grid, dims.CellDim, dims.KDim, extend={dims.KDim: 1})

model/atmosphere/advection/tests/advection/stencil_tests/test_compute_vertical_tracer_flux_upwind.py

@@ -41,7 +41,7 @@ def reference(
         )
         return dict(p_upflux=p_upflux)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         p_mflx_contra_v = data_alloc.random_field(

model/atmosphere/advection/tests/advection/stencil_tests/test_integrate_tracer_density_horizontally.py

@@ -61,7 +61,7 @@ def reference(
             z_tracer_new_dsl=z_tracer_new_dsl,
         )
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_mass_flx_e = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         geofac_div = data_alloc.random_field(grid, dims.CellDim, dims.C2EDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_integrate_tracer_horizontally.py

@@ -45,7 +45,7 @@ def reference(
         ) / rhodz_new
         return dict(tracer_new_hor=tracer_new_hor)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_mflx_tracer_h = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         deepatmo_divh = data_alloc.random_field(grid, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_integrate_tracer_vertically.py

@@ -58,7 +58,7 @@ def reference(
 
         return dict(tracer_new=tracer_new)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         tracer_now = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         rhodz_now = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_limit_vertical_parabola_semi_monotonically.py

@@ -47,7 +47,7 @@ def reference(
         )
         return dict(p_face_up=q_face_up, p_face_low=q_face_low)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         l_limit = data_alloc.random_mask(grid, dims.CellDim, dims.KDim, dtype=gtx.int32)
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_limit_vertical_slope_semi_monotonically.py

@@ -39,7 +39,7 @@ def reference(
         slope = np.where(z_slope[:, 1:-1] >= 0.0, slope_l, -slope_l)
         return dict(z_slope=slope)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         z_slope = data_alloc.random_field(grid, dims.CellDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_postprocess_antidiffusive_cell_fluxes_and_min_max.py

@@ -54,7 +54,7 @@ def reference(
             z_tracer_min=z_tracer_min_out,
         )
 
-    @pytest.fixture()
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         hi_bound, lo_bound = 3, 1
         refin_ctrl = data_alloc.constant_field(grid, 2, dims.CellDim, dtype=gtx.int32)

model/atmosphere/advection/tests/advection/stencil_tests/test_prepare_ffsl_flux_area_patches_list.py

@@ -1470,7 +1470,7 @@ def reference(
             dreg_patch2_4_lat_vmask=dreg_patch2_4_lat_vmask,
         )
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid) -> dict:
         famask_int = data_alloc.random_mask(grid, dims.EdgeDim, dims.KDim, dtype=gtx.int32)
         p_vn = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_prepare_numerical_quadrature_for_cubic_reconstruction.py

@@ -485,7 +485,7 @@ def reference(
             p_dreg_area_out=p_dreg_area_out,
         )
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_coords_dreg_v_1_x = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)
         p_coords_dreg_v_2_x = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_prepare_numerical_quadrature_list_for_cubic_reconstruction.py

@@ -519,7 +519,7 @@ def reference(
             p_dreg_area=p_dreg_area,
         )
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         famask_int = data_alloc.constant_field(grid, 1, dims.EdgeDim, dims.KDim, dtype=gtx.int32)
         p_coords_dreg_v_1_x = data_alloc.random_field(grid, dims.EdgeDim, dims.KDim)

model/atmosphere/advection/tests/advection/stencil_tests/test_reconstruct_cubic_coefficients_svd.py

@@ -304,7 +304,7 @@ def reference(
             p_coeff_10_dsl=p_coeff_10_dsl,
         )
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         p_cc = data_alloc.random_field(grid, dims.CellDim, dims.KDim)
         lsq_pseudoinv_1_field = data_alloc.random_field(grid, dims.CellDim, dims.C2E2C2E2CDim)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_apply_diffusion_to_theta_and_exner.py

@@ -75,7 +75,7 @@ def reference(
 
         return dict(theta_v=theta_v, exner=exner)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid):
         pytest.xfail(
             "stencil segfaults with GTFN and it is not used in diffusion: it is missing an if condition"

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_apply_diffusion_to_vn.py

@@ -115,7 +115,7 @@ def reference(
 
         return dict(vn=vn)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         u_vert = data_alloc.random_field(grid, dims.VertexDim, dims.KDim)
         v_vert = data_alloc.random_field(grid, dims.VertexDim, dims.KDim)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_apply_diffusion_to_w_and_compute_horizontal_gradients_for_turbulence.py

@@ -118,7 +118,7 @@ def reference(
         out_dwdy[subset] = dwdy[subset]
         return dict(w=out_w, dwdx=out_dwdx, dwdy=out_dwdy)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         nrdmax = 13
         cell_domain = h_grid.domain(dims.CellDim)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_apply_nabla2_and_nabla4_global_to_vn.py

@@ -34,7 +34,7 @@ class TestApplyNabla2AndNabla4GlobalToVn(StencilTest):
     PROGRAM = apply_nabla2_and_nabla4_global_to_vn
     OUTPUTS = ("vn",)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid):
         area_edge = random_field(grid, dims.EdgeDim, dtype=wpfloat)
         kh_smag_e = random_field(grid, dims.EdgeDim, dims.KDim, dtype=vpfloat)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_apply_nabla2_and_nabla4_to_vn.py

@@ -42,7 +42,7 @@ class TestApplyNabla2AndNabla4ToVn(StencilTest):
     PROGRAM = apply_nabla2_and_nabla4_to_vn
     OUTPUTS = ("vn",)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid):
         area_edge = random_field(grid, dims.EdgeDim, dtype=wpfloat)
         kh_smag_e = random_field(grid, dims.EdgeDim, dims.KDim, dtype=vpfloat)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_apply_nabla2_to_vn_in_lateral_boundary.py

@@ -33,7 +33,7 @@ class TestApplyNabla2ToVnInLateralBoundary(StencilTest):
     PROGRAM = apply_nabla2_to_vn_in_lateral_boundary
     OUTPUTS = ("vn",)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid):
         fac_bdydiff_v = wpfloat("5.0")
         z_nabla2_e = random_field(grid, dims.EdgeDim, dims.KDim, dtype=wpfloat)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_apply_nabla2_to_w.py

@@ -51,7 +51,7 @@ def reference(
         w = apply_nabla2_to_w_numpy(connectivities, area, z_nabla2_c, geofac_n2s, w, diff_multfac_w)
         return dict(w=w)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid):
         area = random_field(grid, dims.CellDim, dtype=wpfloat)
         z_nabla2_c = random_field(grid, dims.CellDim, dims.KDim, dtype=vpfloat)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_apply_nabla2_to_w_in_upper_damping_layer.py

@@ -34,7 +34,7 @@ class TestApplyNabla2ToWInUpperDampingLayer(StencilTest):
     PROGRAM = apply_nabla2_to_w_in_upper_damping_layer
     OUTPUTS = ("w",)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid):
         w = random_field(grid, dims.CellDim, dims.KDim, dtype=wpfloat)
         diff_multfac_n2w = random_field(grid, dims.KDim, dtype=wpfloat)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_calculate_diagnostics_for_turbulence.py

@@ -47,7 +47,7 @@ def reference(
         )
         return dict(div_ic=div_ic, hdef_ic=hdef_ic)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid):
         wgtfac_c = random_field(grid, dims.CellDim, dims.KDim, dtype=vpfloat)
         div = random_field(grid, dims.CellDim, dims.KDim, dtype=vpfloat)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_calculate_horizontal_gradients_for_turbulence.py

@@ -51,7 +51,7 @@ def reference(
         )
         return dict(dwdx=dwdx, dwdy=dwdy)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid):
         w = data_alloc.random_field(grid, dims.CellDim, dims.KDim, dtype=wpfloat)
         geofac_grg_x = data_alloc.random_field(grid, dims.CellDim, dims.C2E2CODim, dtype=wpfloat)

model/atmosphere/diffusion/tests/diffusion/stencil_tests/test_calculate_nabla2_and_smag_coefficients_for_vn.py

@@ -173,7 +173,7 @@ def reference(
 
         return dict(kh_smag_e=kh_smag_e_out, kh_smag_ec=kh_smag_ec_out, z_nabla2_e=z_nabla2_e_out)
 
-    @pytest.fixture
+    @pytest.fixture(scope="class")
     def input_data(self, grid: base.Grid) -> dict:
         u_vert = data_alloc.random_field(grid, dims.VertexDim, dims.KDim, dtype=ta.vpfloat)
         v_vert = data_alloc.random_field(grid, dims.VertexDim, dims.KDim, dtype=ta.vpfloat)