Merge pull request #21657 from iamnapo/napo/0I_zeroinsert

Fixed zero insertion when concatenate sparse matrices with 0*I

Author: Sacha0

base/sparse/sparsematrix.jl

@@ -1430,6 +1430,9 @@ speye_scaled(diag, m::Integer, n::Integer) = speye_scaled(typeof(diag), diag, m,
 
 function speye_scaled(T, diag, m::Integer, n::Integer)
     ((m < 0) || (n < 0)) && throw(ArgumentError("invalid array dimensions"))
+    if iszero(diag)
+        return SparseMatrixCSC(m, n, ones(Int, n+1), Vector{Int}(0), Vector{T}(0))
+    end
     nnz = min(m,n)
     colptr = Vector{Int}(1+n)
     colptr[1:nnz+1] = 1:nnz+1

test/sparse/sparse.jl

@@ -45,14 +45,18 @@ do33 = ones(3)
 end
 
 @testset "concatenation tests" begin
+    sp33 = speye(3, 3)
+
     @testset "horizontal concatenation" begin
         @test all([se33 se33] == sparse([1, 2, 3, 1, 2, 3], [1, 2, 3, 4, 5, 6], ones(6)))
+        @test length(([sp33 0I]).nzval) == 3
     end
 
     @testset "vertical concatenation" begin
         @test all([se33; se33] == sparse([1, 4, 2, 5, 3, 6], [1, 1, 2, 2, 3, 3], ones(6)))
         se33_32bit = convert(SparseMatrixCSC{Float32,Int32}, se33)
         @test all([se33; se33_32bit] == sparse([1, 4, 2, 5, 3, 6], [1, 1, 2, 2, 3, 3], ones(6)))
+        @test length(([sp33; 0I]).nzval) == 3
     end
 
     se44 = speye(4)
@@ -62,6 +66,7 @@ end
     se77 = speye(7)
     @testset "h+v concatenation" begin
         @test all([se44 sz42 sz41; sz34 se33] == se77)
+        @test length(([sp33 0I; 1I 0I]).nzval) == 6
     end
 
     @testset "blkdiag concatenation" begin