https://github.com/SciML/SciMLOperators.jl/issues/107

Author: vpuri3

src/SciMLOperators.jl

@@ -17,7 +17,7 @@ import Base: +, -, *, /, \, ∘, ==, conj, exp, kron
 import Base: iszero, inv, adjoint, transpose, size, convert
 import LinearAlgebra: mul!, ldiv!, lmul!, rmul!, factorize
 import LinearAlgebra: Matrix, Diagonal
-import SparseArrays: sparse
+import SparseArrays: sparse, issparse
 
 """
 $(TYPEDEF)

src/matrix.jl

@@ -52,6 +52,7 @@ isconstant(L::MatrixOperator) = L.update_func == DEFAULT_UPDATE_FUNC
 Base.iszero(L::MatrixOperator) = iszero(L.A)
 
 SparseArrays.sparse(L::MatrixOperator) = sparse(L.A)
+SparseArrays.issparse(L::MatrixOperator) = issparse(L.A)
 
 # TODO - add tests for MatrixOperator indexing
 # propagate_inbounds here for the getindex fallback