Zero nonzeros?

[dpo]

This is a follow-up of #22 where I try to resolve the issue by multiplying explicitly. However, the following simple example suggests there are no nonzeros in the Jacobian:

julia> function fun!(in, out)
         out .= 3 * in
         return out
       end
fun! (generic function with 1 method)

julia> sparsity_pattern = sparsity!(fun!, input, output)
Explored path: SparsityDetection.Path(Bool[], 1)
30×30 SparseMatrixCSC{Bool,Int64} with 0 stored entries

We expect nonzeros on the diagonal.

[shashi]

The convention is first argument is the output, second is the input.

It works.