FillMatrix times vector returns FillVector

Project.toml

@@ -1,6 +1,6 @@
 name = "FillArrays"
 uuid = "1a297f60-69ca-5386-bcde-b61e274b549b"
-version = "1.11"
+version = "1.12.0"
 
 [deps]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"

src/fillalgebra.jl

@@ -102,9 +102,17 @@ for MT in (:(AbstractMatrix{T}), :(Transpose{<:Any, <:AbstractMatrix{T}}), :(Adj
             :(AbstractTriangular{T}))
     @eval *(a::$MT, b::AbstractZerosVector) where {T} = mult_zeros(a, b)
 end
-*(a::Transpose{<:Any, <:AbstractVector}, b::AbstractZerosMatrix) = transpose(transpose(b) * parent(a))
-*(a::Adjoint{<:Any, <:AbstractVector}, b::AbstractZerosMatrix) = adjoint(adjoint(b) * parent(a))
+for T in (:AbstractZerosMatrix, :AbstractFillMatrix)
+    @eval begin
+        *(a::Transpose{<:Any, <:AbstractVector}, b::$T) = transpose(transpose(b) * parent(a))
+        *(a::Adjoint{<:Any, <:AbstractVector}, b::$T) = adjoint(adjoint(b) * parent(a))
+    end
+end
 *(a::AbstractZerosMatrix, b::AbstractVector) = mult_zeros(a, b)
+function *(F::AbstractFillMatrix, v::AbstractVector)
+    check_matmul_sizes(F, v)
+    Fill(getindex_value(F) * sum(v), (axes(F,1),))
+end
 
 function lmul_diag(a::Diagonal, b)
     size(a,2) == size(b,1) || throw(DimensionMismatch("A has dimensions $(size(a)) but B has dimensions $(size(b))"))
@@ -322,7 +330,7 @@ function _adjvec_mul_zeros(a, b)
     return a1 * b[1]
 end
 
-for MT in (:AbstractMatrix, :AbstractTriangular, :(Adjoint{<:Any,<:TransposeAbsVec}))
+for MT in (:AbstractMatrix, :AbstractTriangular, :(Adjoint{<:Any,<:TransposeAbsVec}), :AbstractFillMatrix)
     @eval *(a::AdjointAbsVec{<:Any,<:AbstractZerosVector}, b::$MT) = (b' * a')'
 end
 # ambiguity
@@ -332,7 +340,7 @@ function *(a::AdjointAbsVec{<:Any,<:AbstractZerosVector}, b::TransposeAbsVec{<:A
     a * b2
 end
 *(a::AdjointAbsVec{<:Any,<:AbstractZerosVector}, b::AbstractZerosMatrix) = (b' * a')'
-for MT in (:AbstractMatrix, :AbstractTriangular, :(Transpose{<:Any,<:AdjointAbsVec}))
+for MT in (:AbstractMatrix, :AbstractTriangular, :(Transpose{<:Any,<:AdjointAbsVec}), :AbstractFillMatrix)
     @eval *(a::TransposeAbsVec{<:Any,<:AbstractZerosVector}, b::$MT) = transpose(transpose(b) * transpose(a))
 end
 *(a::TransposeAbsVec{<:Any,<:AbstractZerosVector}, b::AbstractZerosMatrix) = transpose(transpose(b) * transpose(a))

test/runtests.jl

@@ -1640,14 +1640,16 @@ end
 
             @test Fill(2,3)*A ≈ Vector(Fill(2,3))*A
             @test Fill(2,0)*A ≈ Vector(Fill(2,0))*A
-            @test Fill(2,3,mA)*A ≈ Matrix(Fill(2,3,mA))*A
-            @test Fill(2,3,la)*a ≈ Matrix(Fill(2,3,la))*a
+            @test Fill(2,3,mA)*A ≈ mul!(similar(A, 3,nA), Fill(2,3,mA), A) ≈ Matrix(Fill(2,3,mA))*A
+            @test Fill(2,3,la)*a ≈ mul!(similar(a, 3), Fill(2,3,la), a) ≈ Matrix(Fill(2,3,la))*a
+            @test Fill(2,3,la)*a isa Fill
             @test Ones(3)*A ≈ Vector(Ones(3))*A
-            @test Ones(3,mA)*A ≈ Matrix(Ones(3,mA))*A
-            @test Ones(3,la)*a ≈ Matrix(Ones(3,la))*a
+            @test Ones(3,mA)*A ≈ mul!(similar(A, 3, nA), Ones(3,mA), A) ≈ Matrix(Ones(3,mA))*A
+            @test Ones(3,la)*a ≈ mul!(similar(a, 3), Ones(3,la), a) ≈ Matrix(Ones(3,la))*a
+            @test Ones(3,la)*a isa Fill
             @test Zeros(3)*A  ≡ Zeros(3,nA)
-            @test Zeros(3,mA)*A == Zeros(3,nA)
-            @test Zeros(3,la)*a == Zeros(3)
+            @test Zeros(3,mA)*A == mul!(similar(A, 3, nA), Zeros(3,mA), A) == Zeros(3,nA)
+            @test Zeros(3,la)*a == mul!(similar(A, 3), Zeros(3,la), a) == Zeros(3)
 
             @test A*Fill(2,nA) ≈ A*Vector(Fill(2,nA))
             @test A*Fill(2,nA,1) ≈ A*Matrix(Fill(2,nA,1))
@@ -1669,6 +1671,17 @@ end
 
             @test Zeros(la)' * Transpose(Adjoint(a)) == 0.0
 
+            F = Fill(2, mA, 3)
+            @test transpose(A) * F ≈ transpose(Fill(2, 3, mA) * A)
+            F = Fill(2, la, 3)
+            FS = Fill(2, (Base.OneTo(la), SOneTo(3)))
+            @testset for (adjf, adjT) in ((transpose, Transpose), (adjoint, Adjoint))
+                @test adjf(a) * F ≈ adjf(Fill(2, 3, la) * a)
+                @test adjf(a) * F isa adjT{<:Any, <:Fill{<:Any,1}}
+                @test adjf(a) * FS ≈ adjf(Fill(2, 3, la) * a)
+                @test axes(adjf(a) * FS, 2) == SOneTo(3)
+            end
+
             w = zeros(mA)
             @test mul!(w, A, Fill(2,nA), true, false) ≈ A * fill(2,nA)
             w .= 2