Bugfix for zero matrix in A_ldiv_B! for QRPivoted (JuliaLang#22831)

* Bugfix for zero matrix in A_ldiv_B! for QRPivoted. * Address review comments.
halleysfifthinc · Jul 17, 2017 · bf47fd9 · bf47fd9
1 parent 5535ecb
commit bf47fd9
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Showing 2 changed files with 14 additions and 2 deletions.
diff --git a/base/linalg/qr.jl b/base/linalg/qr.jl
@@ -704,9 +704,13 @@ function A_ldiv_B!(A::QRPivoted{T}, B::StridedMatrix{T}, rcond::Real) where T<:B
  mA, nA = size(A.factors)
  nr = min(mA,nA)
  nrhs = size(B, 2)
- if nr == 0 return zeros(T, 0, nrhs), 0 end
+ if nr == 0
+ return zeros(T, 0, nrhs), 0
+ end
  ar = abs(A.factors[1])
- if ar == 0 return zeros(T, nr, nrhs), 0 end
+ if ar == 0
+ return zeros(T, nA, nrhs), 0
+ end
  rnk = 1
  xmin = ones(T, 1)
  xmax = ones(T, 1)

diff --git a/test/linalg/qr.jl b/test/linalg/qr.jl
@@ -183,3 +183,11 @@ B = rand(7,2)
 
 # Issue 16520
 @test_throws DimensionMismatch ones(3,2)\(1:5)
+
+# Issue 22810
+let
+ A = zeros(1, 2)
+ B = zeros(1, 1)
+ @test A \ B == zeros(2, 1)
+ @test qrfact(A, Val(true)) \ B == zeros(2, 1)
+end