Update tests

src/deprecated.jl

@@ -1,5 +1,5 @@
 # TODO: remove tests when removed
-@deprecate MahalanobisKernel(; P::AbstractMatrix{<:Real}) transform(SqExponentialKernel(), LinearTransform(cholesky(P).U))
+@deprecate MahalanobisKernel(; P::AbstractMatrix{<:Real}) transform(SqExponentialKernel(), LinearTransform(sqrt(2) .* cholesky(P).U))
 
 # TODO: remove keyword argument `maha` when removed
 @deprecate PiecewisePolynomialKernel{V}(A::AbstractMatrix{<:Real}) where V transform(PiecewisePolynomialKernel{V}(size(A, 1)), LinearTransform(cholesky(A).U))

test/basekernels/maha.jl

@@ -1,6 +1,5 @@
 @testset "maha" begin
     rng = MersenneTwister(123456)
-    x = 2 * rand(rng)
     D_in = 3
     v1 = rand(rng, D_in)
     v2 = rand(rng, D_in)
@@ -9,40 +8,10 @@
     P = Matrix(Cholesky(U, 'U', 0))
     @assert isposdef(P)
 
-    k = MahalanobisKernel(; P=P)
-
-    @test kappa(k, x) == exp(-x)
+    k = @test_deprecated MahalanobisKernel(; P=P)
+    @test k isa TransformedKernel{SqExponentialKernel,<:LinearTransform}
+    @test k.transform.A ≈ sqrt(2) .* U
     @test k(v1, v2) ≈ exp(-sqmahalanobis(v1, v2, P))
-    @test kappa(ExponentialKernel(), x) == kappa(k, x)
-    @test repr(k) == "Mahalanobis Kernel (size(P) = $(size(P)))"
-
-    M1, M2 = rand(rng, 3, 2), rand(rng, 3, 2)
-
-    function FiniteDifferences.to_vec(dist::SqMahalanobis)
-        return vec(dist.qmat), x -> SqMahalanobis(reshape(x, size(dist.qmat)...))
-    end
-    a = rand()
-
-    function test_mahakernel(U::UpperTriangular, v1::AbstractVector, v2::AbstractVector)
-        return MahalanobisKernel(; P=Array(U' * U))(v1, v2)
-    end
-
-    @test all(
-        FiniteDifferences.j′vp(FDM, test_mahakernel, a, U, v1, v2)[1] .≈
-        UpperTriangular(Zygote.pullback(test_mahakernel, U, v1, v2)[2](a)[1]),
-    )
-
-    function test_sqmaha(U::UpperTriangular, v1::AbstractVector, v2::AbstractVector)
-        return SqMahalanobis(Array(U' * U))(v1, v2)
-    end
-
-    @test all(
-        FiniteDifferences.j′vp(FDM, test_sqmaha, a, U, v1, v2)[1] .≈
-        UpperTriangular(Zygote.pullback(test_sqmaha, U, v1, v2)[2](a)[1]),
-    )
-
-    # test_ADs(U -> MahalanobisKernel(P=Array(U' * U)), U, ADs=[:Zygote])
-    @test_broken "Nothing passes (problem with Mahalanobis distance in Distances)"
 
     # Standardised tests.
     @testset "ColVecs" begin
@@ -57,5 +26,4 @@
         x2 = RowVecs(randn(2, D_in))
         TestUtils.test_interface(k, x0, x1, x2)
     end
-    test_params(k, (P,))
 end

test/basekernels/piecewisepolynomial.jl

@@ -4,21 +4,26 @@
     v2 = rand(D)
     maha = Matrix{Float64}(I, D, D)
     v = 3
-    k = PiecewisePolynomialKernel{v}(maha)
 
-    k2 = PiecewisePolynomialKernel(; v=v, maha=maha)
+    k = PiecewisePolynomialKernel(; v=v, d=D)
+    k2 = PiecewisePolynomialKernel{v}(D)
+    k3 = @test_deprecated PiecewisePolynomialKernel{v}(maha)
+    k4 = @test_deprecated PiecewisePolynomialKernel(; v=v, maha=maha)
 
-    @test k2(v1, v2) ≈ k(v1, v2) atol = 1e-5
+    @test k2(v1, v2) == k(v1, v2)
+    @test k3(v1, v2) ≈ k(v1, v2)
+    @test k4(v1, v2) ≈ k(v1, v2)
 
     @test_throws ErrorException PiecewisePolynomialKernel{4}(maha)
+    @test_throws ErrorException PiecewisePolynomialKernel{4}(D)
+    @test_throws ErrorException PiecewisePolynomialKernel{v}(-1)
 
-    @test repr(k) == "Piecewise Polynomial Kernel (v = $(v), size(maha) = $(size(maha)))"
+    @test repr(k) == "Piecewise Polynomial Kernel (v = $(v), ⌊d/2⌋ = $(div(D, 2)))"
 
     # Standardised tests.
     TestUtils.test_interface(k, ColVecs{Float64}; dim_in=2)
     TestUtils.test_interface(k, RowVecs{Float64}; dim_in=2)
-    # test_ADs(maha-> PiecewisePolynomialKernel(v=2, maha = maha), maha)
-    @test_broken "Nothing passes (problem with Mahalanobis distance in Distances)"
+    test_ADs(() -> PiecewisePolynomialKernel{v}(D))
 
-    test_params(k, (maha,))
+    test_params(k, ())
 end