Fiber!(SparseList(Element(Inf)), [2.0, Inf, Inf, 1.0, 3.0, Inf]):
Fiber(SparseList{Int32, Int32}(Element{Inf, Float64, Int32, Vector{Float64}}([2.0, 1.0, 3.0]), 6, [1, 4], [1, 4, 5]))

