length(hess_I) > 0

[renkekuhlmann]

Hi,
I run into the assertion
https://github.com/JuliaOpt/JuMP.jl/blob/d8985728c863725537b98bf1e441b99f86d9c2b5/src/nlp.jl#L284

What does that assertion mean? How can I fix my model? The model uses a lot of nonlinear constraints that are built from nonlinear expressions, which appear as subexpressions in the model output. Is this a problem?

[mlubin]

What does that assertion mean?

That appears to be a bug.

How can I fix my model?

Share an example that reproduces the assertion failure, so that we can fix the bug :).

[renkekuhlmann]

Okay, my bad. In the creation of the nonlinear expression there was an ==. I used that expression then to create a constraint like expr == 0. So there where two ==. I didn't noticed that because the expressions are printed just as subexpression[801] - 0.0 = 0 in the model output etc.