Stricter checks, fix left_orth trunc, test trunc

Author: mtfishman

src/factorizations/orthnull.jl

@@ -14,27 +14,56 @@ function MatrixAlgebraKit.initialize_output(
 )
   return nothing
 end
-function MatrixAlgebraKit.check_input(
-  ::typeof(left_orth!), A::AbstractBlockSparseMatrix, F::Nothing
-)
+function MatrixAlgebraKit.check_input(::typeof(left_orth!), A::AbstractBlockSparseMatrix, F)
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`left_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
   return nothing
 end
 
 function MatrixAlgebraKit.left_orth_qr!(A::AbstractBlockSparseMatrix, F, alg)
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`left_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
   alg′ = select_algorithm(qr_compact!, A, alg)
   return qr_compact!(A, alg′)
 end
 function MatrixAlgebraKit.left_orth_polar!(A::AbstractBlockSparseMatrix, F, alg)
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`left_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
   alg′ = select_algorithm(left_polar!, A, alg)
   return left_polar!(A, alg′)
 end
 function MatrixAlgebraKit.left_orth_svd!(
   A::AbstractBlockSparseMatrix, F, alg, trunc::Nothing=nothing
 )
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`left_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
   alg′ = select_algorithm(svd_compact!, A, alg)
   U, S, Vᴴ = svd_compact!(A, alg′)
   return U, S * Vᴴ
 end
+function MatrixAlgebraKit.left_orth_svd!(A::AbstractBlockSparseMatrix, F, alg, trunc)
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`left_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
+  alg′ = select_algorithm(svd_compact!, A, alg)
+  alg_trunc = select_algorithm(svd_trunc!, A, alg′; trunc)
+  U, S, Vᴴ = svd_trunc!(A, alg_trunc)
+  return U, S * Vᴴ
+end
 
 function MatrixAlgebraKit.initialize_output(
   ::typeof(right_orth!), A::AbstractBlockSparseMatrix
@@ -44,25 +73,50 @@ end
 function MatrixAlgebraKit.check_input(
   ::typeof(right_orth!), A::AbstractBlockSparseMatrix, F::Nothing
 )
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`right_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
   return nothing
 end
 
 function MatrixAlgebraKit.right_orth_lq!(A::AbstractBlockSparseMatrix, F, alg)
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`right_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
   alg′ = select_algorithm(lq_compact!, A, alg)
   return lq_compact!(A, alg′)
 end
 function MatrixAlgebraKit.right_orth_polar!(A::AbstractBlockSparseMatrix, F, alg)
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`right_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
   alg′ = select_algorithm(right_polar!, A, alg)
   return right_polar!(A, alg′)
 end
 function MatrixAlgebraKit.right_orth_svd!(
   A::AbstractBlockSparseMatrix, F, alg, trunc::Nothing=nothing
 )
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`right_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
   alg′ = select_algorithm(svd_compact!, A, alg)
   U, S, Vᴴ = svd_compact!(A, alg′)
   return U * S, Vᴴ
 end
 function MatrixAlgebraKit.right_orth_svd!(A::AbstractBlockSparseMatrix, F, alg, trunc)
+  !isnothing(F) && throw(
+    ArgumentError(
+      "`right_orth!` on block sparse matrices does not support specifying the output"
+    ),
+  )
   alg′ = select_algorithm(svd_compact!, A, alg)
   alg_trunc = select_algorithm(svd_trunc!, A, alg′; trunc)
   U, S, Vᴴ = svd_trunc!(A, alg_trunc)

test/test_factorizations.jl

@@ -250,6 +250,11 @@ end
     @test U * C ≈ A
     @test Matrix(U'U) ≈ LinearAlgebra.I
   end
+
+  U, C = left_orth(A; trunc=(; maxrank=2))
+  @test size(U, 2) ≤ 2
+  @test size(C, 1) ≤ 2
+  @test Matrix(U'U) ≈ LinearAlgebra.I
 end
 
 @testset "right_orth (T=$T)" for T in (Float32, Float64, ComplexF32, ComplexF64)
@@ -262,4 +267,9 @@ end
     @test C * U ≈ A
     @test Matrix(U * U') ≈ LinearAlgebra.I
   end
+
+  C, U = right_orth(A; trunc=(; maxrank=2))
+  @test size(C, 2) ≤ 2
+  @test size(U, 1) ≤ 2
+  @test Matrix(U * U') ≈ LinearAlgebra.I
 end