The types of optimisation problems you can create from a given set of
constraints and objectives, based on primal and dual formulations.
Dual here means usually (?) means the Legendre-Fenchel dual
in my field, but there are also the Lagrange and Wolfe duals,
however these work.
I thought the Lagrange dual was the online one? KKT conditions and all that?
Much to learn.
TBD. Discuss role of math:L_p norms.