Speedup matrix multiplications

src/fillalgebra.jl

@@ -1,3 +1,10 @@
+const FillVector{F,A} = Fill{F,1,A}
+const FillMatrix{F,A} = Fill{F,2,A}
+const OnesVector{F,A} = Ones{F,1,A}
+const OnesMatrix{F,A} = Ones{F,2,A}
+const ZerosVector{F,A} = Zeros{F,1,A}
+const ZerosMatrix{F,A} = Zeros{F,2,A}
+
 ## vec
 
 vec(a::Ones{T}) where T = Ones{T}(length(a))
@@ -77,8 +84,10 @@ end
 
 *(a::Zeros{<:Any,1}, b::AbstractMatrix) = mult_zeros(a, b)
 *(a::Zeros{<:Any,2}, b::AbstractMatrix) = mult_zeros(a, b)
+*(a::Zeros{<:Any,2}, b::AbstractTriangular) = mult_zeros(a, b)
 *(a::AbstractMatrix, b::Zeros{<:Any,1}) = mult_zeros(a, b)
 *(a::AbstractMatrix, b::Zeros{<:Any,2}) = mult_zeros(a, b)
+*(a::AbstractTriangular, b::Zeros{<:Any,2}) = mult_zeros(a, b)
 *(a::Zeros{<:Any,1}, b::AbstractVector) = mult_zeros(a, b)
 *(a::Zeros{<:Any,2}, b::AbstractVector) = mult_zeros(a, b)
 *(a::AbstractVector, b::Zeros{<:Any,2}) = mult_zeros(a, b)
@@ -87,36 +96,65 @@ end
 *(a::Zeros{<:Any,2}, b::Diagonal) = mult_zeros(a, b)
 *(a::Diagonal, b::Zeros{<:Any,1}) = mult_zeros(a, b)
 *(a::Diagonal, b::Zeros{<:Any,2}) = mult_zeros(a, b)
-function *(a::Diagonal, b::AbstractFill{<:Any,2}) 
+
+function *(a::Diagonal, b::AbstractFill{T,2}) where T 
     size(a,2) == size(b,1) || throw(DimensionMismatch("A has dimensions $(size(a)) but B has dimensions $(size(b))"))
     a.diag .* b # use special broadcast
 end
-function *(a::AbstractFill{<:Any,2}, b::Diagonal) 
+function *(a::AbstractFill{T,2}, b::Diagonal) where T
     size(a,2) == size(b,1) || throw(DimensionMismatch("A has dimensions $(size(a)) but B has dimensions $(size(b))"))
     a .* permutedims(b.diag) # use special broadcast
 end
 
-*(a::Adjoint{T, <:StridedMatrix{T}},   b::Fill{T, 1}) where T = reshape(sum(conj.(parent(a)); dims=1) .* b.value, size(parent(a), 2))
-*(a::Transpose{T, <:StridedMatrix{T}}, b::Fill{T, 1}) where T = reshape(sum(parent(a); dims=1) .* b.value, size(parent(a), 2))
-*(a::StridedMatrix{T}, b::Fill{T, 1}) where T         = reshape(sum(a; dims=2) .* b.value, size(a, 1))
-
-function *(a::Adjoint{T, <:StridedMatrix{T}}, b::Fill{T, 2}) where T
-    fB = similar(parent(a), size(b, 1), size(b, 2))
-    fill!(fB, b.value)
-    return a*fB
+function mult_sum2(x::AbstractMatrix, f::AbstractFill{T,2}) where T
+    axes(x, 2) ≠ axes(f, 1) &&
+        throw(DimensionMismatch("Incompatible matrix multiplication dimensions"))
+    m = size(f, 2)
+    repeat(sum(x, dims=2) * getindex_value(f), 1, m) 
 end
 
-function *(a::Transpose{T, <:StridedMatrix{T}}, b::Fill{T, 2}) where T
-    fB = similar(parent(a), size(b, 1), size(b, 2))
-    fill!(fB, b.value)
-    return a*fB
+function mult_sum1(f::AbstractFill{T,2}, x::AbstractMatrix) where T
+    axes(f, 2) ≠ axes(x, 1) &&
+        throw(DimensionMismatch("Incompatible matrix multiplication dimensions"))
+    m = size(f, 1)
+    repeat(sum(x, dims=1) * getindex_value(f), m, 1) 
 end
 
-function *(a::StridedMatrix{T}, b::Fill{T, 2}) where T
-    fB = similar(a, size(b, 1), size(b, 2))
-    fill!(fB, b.value)
-    return a*fB
-end
+*(x::AbstractMatrix, y::AbstractFill{<:Any,2}) = mult_sum2(x, y)
+*(x::AbstractTriangular, y::AbstractFill{<:Any,2}) = mult_sum2(x, y)
+*(x::AbstractFill{<:Any,2}, y::AbstractMatrix) = mult_sum1(x, y)
+*(x::AbstractFill{<:Any,2}, y::AbstractTriangular) = mult_sum1(x, y)
+
+
+### These methods are faster for small n #############
+# function *(a::Adjoint{T, <:StridedMatrix{T}}, b::Fill{T, 2}) where T
+#     fB = similar(parent(a), size(b, 1), size(b, 2))
+#     fill!(fB, b.value)
+#     return a*fB
+# end
+
+# function *(a::Transpose{T, <:StridedMatrix{T}}, b::Fill{T, 2}) where T
+#     fB = similar(parent(a), size(b, 1), size(b, 2))
+#     fill!(fB, b.value)
+#     return a*fB
+# end
+
+# function *(a::StridedMatrix{T}, b::Fill{T, 2}) where T
+#     fB = similar(a, size(b, 1), size(b, 2))
+#     fill!(fB, b.value)
+#     return a*fB
+# end
+
+## Matrix-Vector multiplication
+
+*(a::Adjoint{T, <:StridedMatrix{T}},   b::Fill{T, 1}) where T = 
+    reshape(sum(conj.(parent(a)); dims=1) .* b.value, size(parent(a), 2))
+*(a::Transpose{T, <:StridedMatrix{T}}, b::Fill{T, 1}) where T = 
+    reshape(sum(parent(a); dims=1) .* b.value, size(parent(a), 2))
+*(a::StridedMatrix{T}, b::Fill{T, 1}) where T = 
+    reshape(sum(a; dims=2) .* b.value, size(a, 1))
+
+
 function _adjvec_mul_zeros(a::Adjoint{T}, b::Zeros{S, 1}) where {T, S}
     la, lb = length(a), length(b)
     if la ≠ lb

test/runtests.jl

@@ -1028,6 +1028,20 @@ end
     @test E*(1:5) ≡ 1.0:5.0
     @test (1:5)'E == (1.0:5)'
     @test E*E ≡ E
+
+    # Adjoint / Transpose / Triangular / Symmetric / Hermitian
+    for x in [transpose(rand(2, 2)), 
+              adjoint(rand(2,2)),
+              UpperTriangular(rand(2,2)),
+              Symmetric(rand(2,2)),
+              Hermitian(rand(2,2))]
+        @test x * Ones(2, 2) isa Matrix
+        @test Ones(2, 2) * x isa Matrix
+        @test x * Zeros(2, 2) isa Zeros
+        @test Zeros(2, 2) * x isa Zeros
+        @test x * Fill(1., 2, 2) isa Matrix
+        @test Fill(1., 2, 2) * x isa Matrix
+    end
 end
 
 @testset "count" begin