Outer Constructors (#289)

* Use outer constructors

* Bump patch

* Fix typo

Author: willtebbutt

Project.toml

@@ -1,6 +1,6 @@
 name = "KernelFunctions"
 uuid = "ec8451be-7e33-11e9-00cf-bbf324bd1392"
-version = "0.10.0"
+version = "0.10.1"
 
 [deps]
 ChainRulesCore = "d360d2e6-b24c-11e9-a2a3-2a2ae2dbcce4"

src/basekernels/cosine.jl

@@ -13,12 +13,10 @@ By default, ``d`` is the Euclidean metric ``d(x, x') = \\|x - x'\\|_2``.
 """
 struct CosineKernel{M} <: SimpleKernel
     metric::M
-
-    function CosineKernel(; metric=Euclidean())
-        return new{typeof(metric)}(metric)
-    end
 end
 
+CosineKernel(; metric=Euclidean()) = CosineKernel(metric)
+
 kappa(::CosineKernel, d::Real) = cospi(d)
 
 metric(k::CosineKernel) = k.metric

src/basekernels/exponential.jl

@@ -16,12 +16,10 @@ See also: [`GammaExponentialKernel`](@ref)
 """
 struct SqExponentialKernel{M} <: SimpleKernel
     metric::M
-
-    function SqExponentialKernel(; metric=Euclidean())
-        return new{typeof(metric)}(metric)
-    end
 end
 
+SqExponentialKernel(; metric=Euclidean()) = SqExponentialKernel(metric)
+
 kappa(::SqExponentialKernel, d::Real) = exp(-d^2 / 2)
 kappa(::SqExponentialKernel{<:Euclidean}, d²::Real) = exp(-d² / 2)
 
@@ -74,12 +72,10 @@ See also: [`GammaExponentialKernel`](@ref)
 """
 struct ExponentialKernel{M} <: SimpleKernel
     metric::M
-
-    function ExponentialKernel(; metric=Euclidean())
-        return new{typeof(metric)}(metric)
-    end
 end
 
+ExponentialKernel(; metric=Euclidean()) = ExponentialKernel(metric)
+
 kappa(::ExponentialKernel, d::Real) = exp(-d)
 
 metric(k::ExponentialKernel) = k.metric
@@ -129,12 +125,16 @@ struct GammaExponentialKernel{Tγ<:Real,M} <: SimpleKernel
     γ::Vector{Tγ}
     metric::M
 
-    function GammaExponentialKernel(; gamma::Real=1.0, γ::Real=gamma, metric=Euclidean())
+    function GammaExponentialKernel(γ::Real, metric)
         @check_args(GammaExponentialKernel, γ, zero(γ) < γ ≤ 2, "γ ∈ (0, 2]")
         return new{typeof(γ),typeof(metric)}([γ], metric)
     end
 end
 
+function GammaExponentialKernel(; gamma::Real=1.0, γ::Real=gamma, metric=Euclidean())
+    return GammaExponentialKernel(γ, metric)
+end
+
 @functor GammaExponentialKernel
 
 kappa(κ::GammaExponentialKernel, d::Real) = exp(-d^first(κ.γ))

src/basekernels/fbm.jl

@@ -14,12 +14,14 @@ k(x, x'; h) =  \\frac{\\|x\\|_2^{2h} + \\|x'\\|_2^{2h} - \\|x - x'\\|^{2h}}{2}.
 """
 struct FBMKernel{T<:Real} <: Kernel
     h::Vector{T}
-    function FBMKernel(; h::Real=0.5)
+    function FBMKernel(h::Real)
         @check_args(FBMKernel, h, zero(h) ≤ h ≤ one(h), "h ∈ [0, 1]")
         return new{typeof(h)}([h])
     end
 end
 
+FBMKernel(; h::Real=0.5) = FBMKernel(h)
+
 @functor FBMKernel
 
 function (κ::FBMKernel)(x::AbstractVector{<:Real}, y::AbstractVector{<:Real})

src/basekernels/matern.jl

@@ -23,12 +23,14 @@ struct MaternKernel{Tν<:Real,M} <: SimpleKernel
     ν::Vector{Tν}
     metric::M
 
-    function MaternKernel(; nu::Real=1.5, ν::Real=nu, metric=Euclidean())
+    function MaternKernel(ν::Real, metric)
         @check_args(MaternKernel, ν, ν > zero(ν), "ν > 0")
         return new{typeof(ν),typeof(metric)}([ν], metric)
     end
 end
 
+MaternKernel(; nu::Real=1.5, ν::Real=nu, metric=Euclidean()) = MaternKernel(ν, metric)
+
 @functor MaternKernel
 
 @inline function kappa(κ::MaternKernel, d::Real)
@@ -67,12 +69,10 @@ See also: [`MaternKernel`](@ref)
 """
 struct Matern32Kernel{M} <: SimpleKernel
     metric::M
-
-    function Matern32Kernel(; metric=Euclidean())
-        return new{typeof(metric)}(metric)
-    end
 end
 
+Matern32Kernel(; metric=Euclidean()) = Matern32Kernel(metric)
+
 kappa(::Matern32Kernel, d::Real) = (1 + sqrt(3) * d) * exp(-sqrt(3) * d)
 
 metric(k::Matern32Kernel) = k.metric
@@ -100,12 +100,10 @@ See also: [`MaternKernel`](@ref)
 """
 struct Matern52Kernel{M} <: SimpleKernel
     metric::M
-
-    function Matern52Kernel(; metric=Euclidean())
-        return new{typeof(metric)}(metric)
-    end
 end
 
+Matern52Kernel(; metric=Euclidean()) = Matern52Kernel(metric)
+
 kappa(::Matern52Kernel, d::Real) = (1 + sqrt(5) * d + 5 * d^2 / 3) * exp(-sqrt(5) * d)
 
 metric(k::Matern52Kernel) = k.metric

src/basekernels/polynomial.jl

@@ -16,12 +16,14 @@ See also: [`PolynomialKernel`](@ref)
 struct LinearKernel{Tc<:Real} <: SimpleKernel
     c::Vector{Tc}
 
-    function LinearKernel(; c::Real=0.0)
+    function LinearKernel(c::Real)
         @check_args(LinearKernel, c, c >= zero(c), "c ≥ 0")
         return new{typeof(c)}([c])
     end
 end
 
+LinearKernel(; c::Real=0.0) = LinearKernel(c)
+
 @functor LinearKernel
 
 kappa(κ::LinearKernel, xᵀy::Real) = xᵀy + first(κ.c)

src/basekernels/rational.jl

@@ -19,12 +19,16 @@ struct RationalKernel{Tα<:Real,M} <: SimpleKernel
     α::Vector{Tα}
     metric::M
 
-    function RationalKernel(; alpha::Real=2.0, α::Real=alpha, metric=Euclidean())
+    function RationalKernel(α::Real, metric)
         @check_args(RationalKernel, α, α > zero(α), "α > 0")
         return new{typeof(α),typeof(metric)}([α], metric)
     end
 end
 
+function RationalKernel(; alpha::Real=2.0, α::Real=alpha, metric=Euclidean())
+    return RationalKernel(α, metric)
+end
+
 @functor RationalKernel
 
 function kappa(κ::RationalKernel, d::Real)