norm and zero! based on MemoryLayout (#73)

* norm and zero! based on MemoryLayout

* Update test_layoutarray.jl

Author: dlfivefifty

src/ArrayLayouts.jl

@@ -232,14 +232,20 @@ Base.map(::typeof(copy), D::Diagonal{<:LayoutArray}) = Diagonal(map(copy, D.diag
 Base.permutedims(D::Diagonal{<:Any,<:LayoutVector}) = D
 
 
-zero!(A::AbstractArray{T}) where T = fill!(A,zero(T))
-function zero!(A::AbstractArray{<:AbstractArray})
+zero!(A) = zero!(MemoryLayout(A), A)
+zero!(_, A) = fill!(A,zero(eltype(A)))
+function zero!(_, A::AbstractArray{<:AbstractArray})
     for a in A
         zero!(a)
     end
     A
 end
 
+_norm(_, A, p) = Base.invoke(norm, Tuple{Any,Real}, A, p)
+LinearAlgebra.norm(A::LayoutArray, p::Real=2) = _norm(MemoryLayout(A), A, p)
+LinearAlgebra.norm(A::SubArray{<:Any,N,<:LayoutArray}, p::Real=2) where N = _norm(MemoryLayout(A), A, p)
+
+
 _fill_lmul!(β, A::AbstractArray{T}) where T = iszero(β) ? zero!(A) : lmul!(β, A)
 
 

test/test_layoutarray.jl

@@ -50,6 +50,7 @@ MemoryLayout(::Type{MyVector}) = DenseColumnMajor()
         v = view(a,1:3)
         @test copy(v) == sub_materialize(v) == a[1:3]
         @test dot(v,a) == dot(v,a.A) == dot(a,v) == dot(a.A,v) == dot(v,v) == 14
+        @test norm(v) == norm(a) == norm([1,2,3])
 
         V = view(a',:,1:3)
         @test copy(V) == sub_materialize(V) == (a')[:,1:3]