LinearAlgebra/addmul/mul!(::Matrix{ComplexF64}, ::LinearAlgebra.SymTridiagonal{ComplexF32, V} where V<:AbstractVector{ComplexF32}, ::LinearAlgebra.SymTridiagonal{ComplexF64, V} where V<:AbstractVector{ComplexF64}, α, β)/α = -0.5001434563013438 - 0.7314958405805521im, β = 0.0 + 0.0im @test ≈(collect(returned_mat), exp_val, rtol = rtol, atol = atol)