But I always get this warning, ERROR: UndefVarError: SingleVariable not defined in MathOptInterface
Suggestion: check for spelling errors or missing imports.
Regardless, I don’t recommend that you run the code. What are you trying to do and why? The biobjective algorithm works in theory, but not very well in practice.
Oh I saw this file but I didn’t realize they are relevant. I will try again.
I am writing the master’s thesis, and the topic is to incorporating carbon emissions in multi-stage lot sizing model with stochastic demand. It can be modeled in two ways: 1. minimize cost and carbon emissions as a constraint; 2. minimize cost and carbon emissions same time as a bi-objective model. Both are linear integer problem.
Thank you for asking! And I would appreciate any insights here on my topic
The idea of a bi-objective policy, and that you could use SDDP to build one
The heuristic solution method from the last section.
The least useful part of the paper was the exact solution algorithm, since it relied on the internals of the solver, and was highly susceptible to numerical issues.
I’ve implemented the heuristic as SDDP.train_biobjective, but it isn’t well documented yet.
After training, you can use: SDDP.set_trade_off_weight(model, weight) to fix a particular weight and then simulate like you would with a single-objective problem.
Alternatively, you could also just solve a set of independent SDDP models for different scalarization weights.