Diagonal ambiguities (#172)

* Diagonal ambiguities

* add tests

* add Sub * Diagonal

Author: dlfivefifty

Project.toml

@@ -1,7 +1,7 @@
 name = "ArrayLayouts"
 uuid = "4c555306-a7a7-4459-81d9-ec55ddd5c99a"
 authors = ["Sheehan Olver <[email protected]>"]
-version = "1.3.0"
+version = "1.3.1"
 
 [deps]
 FillArrays = "1a297f60-69ca-5386-bcde-b61e274b549b"

src/mul.jl

@@ -321,10 +321,17 @@ end
 # mul! for subarray of layout matrix
 const SubLayoutMatrix = Union{SubArray{<:Any,2,<:LayoutMatrix}, SubArray{<:Any,2,<:AdjOrTrans{<:Any,<:LayoutMatrix}}}
 
+*(A::Diagonal, B::SubLayoutMatrix) = mul(A, B)
+*(A::SubLayoutMatrix, B::Diagonal) = mul(A, B)
+
 LinearAlgebra.mul!(C::AbstractMatrix, A::SubLayoutMatrix, B::AbstractMatrix, α::Number, β::Number) =
     ArrayLayouts.mul!(C, A, B, α, β)
 LinearAlgebra.mul!(C::AbstractMatrix, A::AbstractMatrix, B::SubLayoutMatrix, α::Number, β::Number) =
     ArrayLayouts.mul!(C, A, B, α, β)
+LinearAlgebra.mul!(C::AbstractMatrix, A::Diagonal, B::SubLayoutMatrix, α::Number, β::Number) =
+    ArrayLayouts.mul!(C, A, B, α, β)
+LinearAlgebra.mul!(C::AbstractMatrix, A::SubLayoutMatrix, B::Diagonal, α::Number, β::Number) =
+    ArrayLayouts.mul!(C, A, B, α, β)
 LinearAlgebra.mul!(C::AbstractMatrix, A::SubLayoutMatrix, B::LayoutMatrix, α::Number, β::Number) =
     ArrayLayouts.mul!(C, A, B, α, β)
 LinearAlgebra.mul!(C::AbstractMatrix, A::LayoutMatrix, B::SubLayoutMatrix, α::Number, β::Number) =

test/test_layoutarray.jl

@@ -508,6 +508,8 @@ MemoryLayout(::Type{MyVector}) = DenseColumnMajor()
             V = view(A, 1:3, 1:3)
             B = randn(3,3)
             x = randn(3)
+            D = Diagonal(1:3)
+
             @test mul!(similar(B), V, B) ≈ A * B
             @test mul!(similar(B), B, V) ≈ B * A
             @test mul!(similar(B), V, V) ≈ A^2
@@ -524,6 +526,10 @@ MemoryLayout(::Type{MyVector}) = DenseColumnMajor()
             @test mul!(MyMatrix(copy(B)), A, V, 2.0, 3.0) ≈ 2A * A + 3B
             @test mul!(copy(x), V, x, 2.0, 3.0) ≈ 2A * x + 3x
 
+            @test D * V == D * A == D * A.A
+            @test V * D == A * D == A.A  * D
+            @test mul!(copy(B), D, A, 2.0, 3.0) ≈ mul!(copy(B), D, V, 2.0, 3.0) ≈ 2D * A + 3B
+            @test mul!(copy(B), A, D, 2.0, 3.0) ≈ mul!(copy(B), V, D, 2.0, 3.0) ≈ 2A * D + 3B
     end
 end