Fix setindex! with ranges (#138) (#349)

* Fix setindex! with ranges (#138)

* Update BandedMatrix.jl

Author: dlfivefifty

Project.toml

@@ -1,6 +1,6 @@
 name = "BandedMatrices"
 uuid = "aae01518-5342-5314-be14-df237901396f"
-version = "0.17.20"
+version = "0.17.21"
 
 [deps]
 ArrayLayouts = "4c555306-a7a7-4459-81d9-ec55ddd5c99a"

src/banded/BandedMatrix.jl

@@ -622,20 +622,7 @@ end
     @boundscheck checkbounds(A, kr, jr)
     @boundscheck checkdimensions(kr, jr, V)
     @boundscheck checkbandmatch(A, V, kr, jr)
-
-    data, u, l = A.data, A.u, A.l
-    jj = 1
-    for j in jr
-        kk = 1
-        for k in kr
-            if -l ≤ j - k ≤ u
-                # we index V manually in column-major order
-                inbands_setindex!(data, u, V[kk, jj], k, j)
-                kk += 1
-            end
-        end
-        jj += 1
-    end
+    copyto!(view(A, kr, jr), V)
     V
 end
 

test/test_banded.jl

@@ -469,5 +469,15 @@ Base.similar(::MyMatrix, ::Type{T}, m::Int, n::Int) where T = MyMatrix{T}(undef,
         A = _BandedMatrix(Fill(1,1,5), Base.Slice(1:4), 1, -1)
         @test summary(A) == "4×5 BandedMatrix{$Int} with bandwidths (1, -1) with data 1×5 Fill{$Int} with indices 1:4×Base.OneTo(5)"
     end
+
+    @testset "setindex! with ranges (#348)" begin
+        n = 10; 
+        X1 = brand(n,n,1,1)
+        B = BandedMatrix(Zeros(2n,2n), (3,3))
+        B[1:2:end,1:2:end] = X1
+        A = zeros(2n,2n)
+        A[1:2:end,1:2:end] = X1
+        @test A == B
+    end
 end