sparse concretizations

Author: ChrisRackauckas

src/derivative_operators/BC_operators.jl

@@ -121,9 +121,19 @@ function LinearAlgebra.Array(Q::AffineBC{T,V}, N::Int) where {T,V}
     return (Array(Q_L), Q_b)
 end
 
-LinearAlgebra.Array(Q::PeriodicBC{T}, N::Int) where T = [transpose(zeros(T, N-1)) one(T); Diagonal(ones(T,N)); one(T) transpose(zeros(T, N-1))]
-#TODO: Concretize DirichletBC
+function SparseArrays.SparseMatrixCSC(Q::AffineBC{T,V}, N::Int) where {T,V}
+    Q_L = [transpose(Q.a_l) transpose(zeros(T, N-length(Q.a_l))); Diagonal(ones(T,N)); transpose(zeros(T, N-length(Q.a_r))) transpose(Q.a_r)]
+    Q_b = [Q.b_l; zeros(T,N); Q.b_r]
+    return (Q_L, Q_b)
+end
+
+function SparseArrays.sparse(Q::AffineBC{T,V}, N::Int) where {T,V}
+    SparseMatrixCSC(Q,N)
+end
 
+LinearAlgebra.Array(Q::PeriodicBC{T}, N::Int) where T = Array([transpose(zeros(T, N-1)) one(T); Diagonal(ones(T,N)); one(T) transpose(zeros(T, N-1))])
+SparseArrays.SparseMatrixCSC(Q::PeriodicBC{T}, N::Int) where T = [transpose(zeros(T, N-1)) one(T); Diagonal(ones(T,N)); one(T) transpose(zeros(T, N-1))]
+SparseArrays.sparse(Q::PeriodicBC{T}, N::Int) where T = SparseMatrixCSC(Q,N)
 
 function LinearAlgebra.Array(Q::BoundaryPaddedVector)
     return [Q.l; Q.u; Q.r]