Remove dependency of Oceananigans on OrthogonalSphericalShellGrids

test/runtests.jl

@@ -32,6 +32,7 @@ include("dependencies_for_runtests.jl")
 end
 
 include("test_tripolar_grid.jl")
+include("test_vector_rotation.jl")
 include("test_zipper_boundary_conditions.jl")
 
 @testset "Model tests..." begin

test/test_vector_rotation.jl

@@ -0,0 +1,136 @@
+# This test is copied from the Cubed Sphere test in Oceananigans.jl (https://github.com/CliMA/Oceananigans.jl/) at:
+# https://github.com/CliMA/Oceananigans.jl/blob/main/test/test_cubed_spheres.jl
+
+using Oceananigans.Operators: intrinsic_vector, extrinsic_vector
+
+# To be used in the test below as `KernelFunctionOperation`s
+@inline intrinsic_vector_x_component(i, j, k, grid, uₑ, vₑ) = 
+    @inbounds intrinsic_vector(i, j, k, grid, uₑ, vₑ)[1]
+
+@inline intrinsic_vector_y_component(i, j, k, grid, uₑ, vₑ) =
+    @inbounds intrinsic_vector(i, j, k, grid, uₑ, vₑ)[2]
+
+@inline extrinsic_vector_x_component(i, j, k, grid, uᵢ, vᵢ) =
+    @inbounds extrinsic_vector(i, j, k, grid, uᵢ, vᵢ)[1]
+
+@inline extrinsic_vector_y_component(i, j, k, grid, uᵢ, vᵢ) =
+    @inbounds extrinsic_vector(i, j, k, grid, uᵢ, vᵢ)[2]
+
+function kinetic_energy(u, v)
+    ke = Field(0.5 * (u * u + v * v))
+    return compute!(ke)
+end
+
+function test_vector_rotation(grid)
+    u = XFaceField(grid)
+    v = YFaceField(grid)
+
+    # Purely longitudinal flow in the extrinsic coordinate system
+    set!(u, 1)
+    set!(v, 0)
+
+    # Convert it to an "Instrinsic" reference frame
+    uᵢ = KernelFunctionOperation{Face, Center, Center}(intrinsic_vector_x_component, grid, u, v)
+    vᵢ = KernelFunctionOperation{Center, Face, Center}(intrinsic_vector_y_component, grid, u, v)
+
+    uᵢ = compute!(Field(uᵢ))
+    vᵢ = compute!(Field(vᵢ))
+
+    # The extrema of u and v, as well as their mean value should
+    # be equivalent on an "intrinsic" frame
+    @test maximum(uᵢ) ≈ maximum(vᵢ)
+    @test minimum(uᵢ) ≈ minimum(vᵢ)
+    @test mean(uᵢ) ≈ mean(vᵢ)
+    @test mean(uᵢ) > 0 # The mean value should be positive
+
+    # Kinetic energy should remain the same
+    KE = kinetic_energy(uᵢ, vᵢ)
+    @test all(on_architecture(CPU(), interior(KE)) .≈ 0.5)
+
+    # Convert it back to a purely zonal velocity (vₑ == 0)
+    uₑ = KernelFunctionOperation{Face, Center, Center}(extrinsic_vector_x_component, grid, uᵢ, vᵢ)
+    vₑ = KernelFunctionOperation{Center, Face, Center}(extrinsic_vector_y_component, grid, uᵢ, vᵢ)
+
+    uₑ = compute!(Field(uₑ))
+    vₑ = compute!(Field(vₑ))
+
+    # Make sure that the flow was converted back to a 
+    # purely zonal flow in the extrensic frame (v ≈ 0)
+    @test all(on_architecture(CPU(), interior(vₑ)) .≈ 0)
+    @test all(on_architecture(CPU(), interior(uₑ)) .≈ 1)
+
+    # Purely meridional flow in the extrinsic coordinate system
+    set!(u, 0)
+    set!(v, 1)
+
+    # Convert it to an "Instrinsic" reference frame
+    uᵢ = KernelFunctionOperation{Face, Center, Center}(intrinsic_vector_x_component, grid, u, v)
+    vᵢ = KernelFunctionOperation{Center, Face, Center}(intrinsic_vector_y_component, grid, u, v)
+
+    uᵢ = compute!(Field(uᵢ))
+    vᵢ = compute!(Field(vᵢ))
+
+    # The extrema of u and v, as well as their mean value should
+    # be equivalent on an "intrinsic" frame
+    @test maximum(uᵢ) ≈ maximum(vᵢ)
+    @test minimum(uᵢ) ≈ minimum(vᵢ)
+    @test mean(uᵢ) ≈ mean(vᵢ)
+    @test mean(vᵢ) > 0 # The mean value should be positive
+
+    # Kinetic energy should remain the same
+    KE = kinetic_energy(uᵢ, vᵢ)
+    @test all(on_architecture(CPU(), interior(KE)) .≈ 0.5)
+
+    # Convert it back to a purely zonal velocity (vₑ == 0)
+    uₑ = KernelFunctionOperation{Face, Center, Center}(extrinsic_vector_x_component, grid, uᵢ, vᵢ)
+    vₑ = KernelFunctionOperation{Center, Face, Center}(extrinsic_vector_y_component, grid, uᵢ, vᵢ)
+
+    uₑ = compute!(Field(uₑ))
+    vₑ = compute!(Field(vₑ))
+
+    # Make sure that the flow was converted back to a 
+    # purely zonal flow in the extrensic frame (v ≈ 0)
+    @test all(on_architecture(CPU(), interior(vₑ)) .≈ 1)
+    @test all(on_architecture(CPU(), interior(uₑ)) .≈ 0)
+
+    # Mixed zonal and meridional flow.
+    set!(u, 0.5)
+    set!(v, 0.5)
+
+    # Convert it to an "Instrinsic" reference frame
+    uᵢ = KernelFunctionOperation{Face, Center, Center}(intrinsic_vector_x_component, grid, u, v)
+    vᵢ = KernelFunctionOperation{Center, Face, Center}(intrinsic_vector_y_component, grid, u, v)
+
+    uᵢ = compute!(Field(uᵢ))
+    vᵢ = compute!(Field(vᵢ))
+
+    # The extrema of u and v, as well as their mean value should
+    # be equivalent on an "intrinsic" frame
+    @test maximum(uᵢ) ≈ maximum(vᵢ)
+    @test minimum(uᵢ) ≈ minimum(vᵢ)
+    @test mean(uᵢ) ≈ mean(vᵢ)
+    @test mean(vᵢ) > 0 # The mean value should be positive
+
+    # Kinetic energy should remain the same
+    KE = kinetic_energy(uᵢ, vᵢ)
+    @test all(on_architecture(CPU(), interior(KE)) .≈ 0.25)
+
+    # Convert it back to a purely zonal velocity (vₑ == 0)
+    uₑ = KernelFunctionOperation{Face, Center, Center}(extrinsic_vector_x_component, grid, uᵢ, vᵢ)
+    vₑ = KernelFunctionOperation{Center, Face, Center}(extrinsic_vector_y_component, grid, uᵢ, vᵢ)
+
+    uₑ = compute!(Field(uₑ))
+    vₑ = compute!(Field(vₑ))
+
+    # Make sure that the flow was converted back to a 
+    # purely zonal flow in the extrensic frame (v ≈ 0)
+    @test all(on_architecture(CPU(), interior(vₑ)) .≈ 0.5)
+    @test all(on_architecture(CPU(), interior(uₑ)) .≈ 0.5)
+end
+
+@testset "Conversion from Intrinsic to Extrinsic reference frame" begin
+    @info "  Testing the conversion of a vector between the Intrinsic and Extrinsic reference frame"
+    grid = TripolarGrid(size = (20, 20, 1), z = (0, 1))
+
+    test_vector_rotation(grid)
+end