Fix Matrix(QRSparseQ) constructor (JuliaLang#26392)

* Fix Matrix(QRSparseQ) constructor

Fixes JuliaLang#26367

* Make sure that size(Q, i) definition covers HessenbergQ

stdlib/LinearAlgebra/src/qr.jl

@@ -502,23 +502,22 @@ AbstractMatrix{T}(Q::QRPackedQ) where {T} = QRPackedQ{T}(Q)
 QRCompactWYQ{S}(Q::QRCompactWYQ) where {S} = QRCompactWYQ(convert(AbstractMatrix{S}, Q.factors), convert(AbstractMatrix{S}, Q.T))
 AbstractMatrix{S}(Q::QRCompactWYQ{S}) where {S} = Q
 AbstractMatrix{S}(Q::QRCompactWYQ) where {S} = QRCompactWYQ{S}(Q)
-Matrix{T}(A::AbstractQ) where {T} = lmul!(A, Matrix{T}(I, size(A.factors, 1), min(size(A.factors)...)))
-Matrix(A::AbstractQ{T}) where {T} = Matrix{T}(A)
-Array{T}(A::AbstractQ) where {T} = Matrix{T}(A)
-Array(A::AbstractQ) = Matrix(A)
-
-size(A::Union{QR,QRCompactWY,QRPivoted}, dim::Integer) = size(getfield(A, :factors), dim)
-size(A::Union{QR,QRCompactWY,QRPivoted}) = size(getfield(A, :factors))
-size(A::AbstractQ, dim::Integer) = 0 < dim ? (dim <= 2 ? size(getfield(A, :factors), 1) : 1) : throw(BoundsError())
-size(A::AbstractQ) = size(A, 1), size(A, 2)
-
-
-function getindex(A::AbstractQ, i::Integer, j::Integer)
- x = zeros(eltype(A), size(A, 1))
+Matrix{T}(Q::AbstractQ) where {T} = lmul!(Q, Matrix{T}(I, size(Q, 1), min(size(Q.factors)...)))
+Matrix(Q::AbstractQ{T}) where {T} = Matrix{T}(Q)
+Array{T}(Q::AbstractQ) where {T} = Matrix{T}(Q)
+Array(Q::AbstractQ) = Matrix(Q)
+
+size(F::Union{QR,QRCompactWY,QRPivoted}, dim::Integer) = size(getfield(F, :factors), dim)
+size(F::Union{QR,QRCompactWY,QRPivoted}) = size(getfield(F, :factors))
+size(Q::AbstractQ, dim::Integer) = size(getfield(Q, :factors), dim == 2 ? 1 : dim)
+size(Q::AbstractQ) = size(Q, 1), size(Q, 2)
+
+function getindex(Q::AbstractQ, i::Integer, j::Integer)
+ x = zeros(eltype(Q), size(Q, 1))
  x[i] = 1
- y = zeros(eltype(A), size(A, 2))
+ y = zeros(eltype(Q), size(Q, 2))
  y[j] = 1
- return dot(x, lmul!(A, y))
+ return dot(x, lmul!(Q, y))
 end
 
 ## Multiplication by Q

stdlib/LinearAlgebra/test/qr.jl

@@ -145,7 +145,7 @@ rectangularQ(Q::LinearAlgebra.AbstractQ) = convert(Array, Q)
  @test_throws DimensionMismatch rmul!(Matrix{eltya}(I, n+1, n+1),q)
  @test rmul!(squareQ(q), adjoint(q)) ≈ Matrix(I, n, n)
  @test_throws DimensionMismatch rmul!(Matrix{eltya}(I, n+1, n+1), adjoint(q))
- @test_throws BoundsError size(q,-1)
+ @test_throws ErrorException size(q,-1)
  @test_throws DimensionMismatch LinearAlgebra.lmul!(q,zeros(eltya,n1+1))
  @test_throws DimensionMismatch LinearAlgebra.lmul!(adjoint(q), zeros(eltya,n1+1))
 
@@ -155,7 +155,7 @@ rectangularQ(Q::LinearAlgebra.AbstractQ) = convert(Array, Q)
  @test_throws DimensionMismatch rmul!(Matrix{eltya}(I, n+1, n+1),q)
  @test rmul!(squareQ(q), adjoint(q)) ≈ Matrix(I, n, n)
  @test_throws DimensionMismatch rmul!(Matrix{eltya}(I, n+1, n+1),adjoint(q))
- @test_throws BoundsError size(q,-1)
+ @test_throws ErrorException size(q,-1)
  @test_throws DimensionMismatch q * Matrix{Int8}(I, n+4, n+4)
  end
  end

stdlib/SuiteSparse/src/spqr.jl

@@ -130,11 +130,14 @@ Base.axes(F::QRSparse) = map(Base.OneTo, size(F))
 struct QRSparseQ{Tv<:CHOLMOD.VTypes,Ti<:Integer} <: LinearAlgebra.AbstractQ{Tv}
  factors::SparseMatrixCSC{Tv,Ti}
  τ::Vector{Tv}
+ n::Int # Number of columns in original matrix
 end
 
 Base.size(Q::QRSparseQ) = (size(Q.factors, 1), size(Q.factors, 1))
 Base.axes(Q::QRSparseQ) = map(Base.OneTo, size(Q))
 
+Matrix{T}(Q::QRSparseQ) where {T} = lmul!(Q, Matrix{T}(I, size(Q, 1), min(size(Q, 1), Q.n)))
+
 # From SPQR manual p. 6
 _default_tol(A::SparseMatrixCSC) =
  20*sum(size(A))*eps(real(eltype(A)))*maximum(norm(view(A, :, i)) for i in 1:size(A, 2))
@@ -305,7 +308,7 @@ julia> F.pcol
 """
 @inline function Base.getproperty(F::QRSparse, d::Symbol)
  if d == :Q
- return QRSparseQ(F.factors, F.τ)
+ return QRSparseQ(F.factors, F.τ, size(F, 2))
  elseif d == :prow
  return invperm(F.rpivinv)
  elseif d == :pcol

stdlib/SuiteSparse/test/spqr.jl

@@ -81,6 +81,11 @@ end
  @test A*xs ≈ A*xd
 end
 
+@testset "Issue 26367" begin
+ A = sparse([0.0 1 0 0; 0 0 0 0])
+ @test Matrix(qr(A).Q) == Matrix(qr(Matrix(A)).Q) == Matrix(I, 2, 2)
+end
+
 @testset "Issue 26368" begin
  A = sparse([0.0 1 0 0; 0 0 0 0])
  F = qr(A)