From 00ad0aa290c716cfb6b312180becae93641dcb5d Mon Sep 17 00:00:00 2001
From: Sheehan Olver <solver@mac.com>
Date: Sun, 3 Dec 2023 14:11:58 +0000
Subject: [PATCH] Support RectDiagonal (#411)

---
 Project.toml               | 2 +-
 src/BandedMatrices.jl      | 2 +-
 src/banded/BandedMatrix.jl | 8 ++++----
 src/interfaceimpl.jl       | 6 +++---
 test/test_interface.jl     | 4 ++++
 5 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/Project.toml b/Project.toml
index 1a28e519..a29a3f75 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,6 +1,6 @@
 name = "BandedMatrices"
 uuid = "aae01518-5342-5314-be14-df237901396f"
-version = "1.2.1"
+version = "1.3"
 
 [deps]
 ArrayLayouts = "4c555306-a7a7-4459-81d9-ec55ddd5c99a"
diff --git a/src/BandedMatrices.jl b/src/BandedMatrices.jl
index 914b97de..5ce905d2 100644
--- a/src/BandedMatrices.jl
+++ b/src/BandedMatrices.jl
@@ -34,7 +34,7 @@ import ArrayLayouts: MemoryLayout, transposelayout, triangulardata,
                     _qr!, _qr, _lu!, _lu, _factorize, AbstractTridiagonalLayout, TridiagonalLayout,
                     BidiagonalLayout, bidiagonaluplo, diagonaldata, supdiagonaldata, subdiagonaldata, copymutable_oftype_layout, dualadjoint
 
-import FillArrays: AbstractFill, getindex_value, _broadcasted_zeros, unique_value, OneElement
+import FillArrays: AbstractFill, getindex_value, _broadcasted_zeros, unique_value, OneElement, RectDiagonal
 
 const libblas = LinearAlgebra.BLAS.libblas
 const liblapack = LinearAlgebra.BLAS.liblapack
diff --git a/src/banded/BandedMatrix.jl b/src/banded/BandedMatrix.jl
index 98aa5b78..ca247744 100644
--- a/src/banded/BandedMatrix.jl
+++ b/src/banded/BandedMatrix.jl
@@ -226,10 +226,10 @@ BandedMatrix{V,C,Base.OneTo{Int}}(Z::Zeros{T,2}, bnds::NTuple{2,Integer}) where
 BandedMatrix{V}(Z::Zeros{T,2}, bnds::NTuple{2,Integer}) where {T,V} =
     _BandedMatrix(zeros(V,max(0,sum(bnds)+1),size(Z,2)),size(Z,1),bnds...)
 
-BandedMatrix(E::Eye{T}, bnds::NTuple{2,Integer}) where T = BandedMatrix{T}(E, bnds)
-function BandedMatrix{T}(E::Eye, bnds::NTuple{2,Integer}) where T
-    ret=BandedMatrix(Zeros{T}(E), bnds)
-    ret[band(0)] .= one(T)
+BandedMatrix(E::RectDiagonal{T}, bnds::NTuple{2,Integer}) where T = BandedMatrix{T}(E, bnds)
+function BandedMatrix{T}(E::RectDiagonal, bnds::NTuple{2,Integer}) where T
+    ret = BandedMatrix(Zeros{T}(E), bnds)
+    ret[band(0)] .= E.diag
     ret
 end
 
diff --git a/src/interfaceimpl.jl b/src/interfaceimpl.jl
index ab791a44..ce22de65 100644
--- a/src/interfaceimpl.jl
+++ b/src/interfaceimpl.jl
@@ -18,9 +18,9 @@ isbanded(::Zeros) = true
 bandwidths(::Zeros) = (-40320,-40320) # 40320 == prod(1:8), used for special cases involving gcd
 inbands_getindex(::Zeros{T}, k::Integer, j::Integer) where T = zero(T)
 
-isbanded(::Eye) = true
-bandwidths(::Eye) = (0,0)
-inbands_getindex(::Eye{T}, k::Integer, j::Integer) where T = one(T)
+isbanded(::RectDiagonal) = true
+bandwidths(::RectDiagonal) = (0,0)
+inbands_getindex(E::RectDiagonal, k::Integer, j::Integer) = E.diag[k]
 
 isbanded(::Diagonal) = true
 bandwidths(::Diagonal) = (0,0)
diff --git a/test/test_interface.jl b/test/test_interface.jl
index 244734d5..7173eaca 100644
--- a/test/test_interface.jl
+++ b/test/test_interface.jl
@@ -59,6 +59,10 @@ LinearAlgebra.fill!(A::PseudoBandedMatrix, v) = fill!(A.data,v)
         @test B * Eye(5) == B
         @test muladd!(2.0, Eye(5), B, 0.0, zeros(5,5)) == 2B
         @test muladd!(2.0, B, Eye(5), 0.0, zeros(5,5)) == 2B
+
+        @test isbanded(2Eye(5,6))
+        @test bandwidths(2Eye(5,6)) == (0,0)
+        @test BandedMatrices.inbands_getindex(2Eye(5,6), 1,1) == 2
     end
 
     @testset "Diagonal" begin