Resources Worth Looking At

Great to see you guys undertake this project, would be nice to have a well maintained lib for these applications.

I am not sure if you are aware of some similar applications and libs, since you didn't mention them in your paper. But here are some refs that might be useful for you.

Anthony worked on some stuff regarding function approximation with adaptivity in both sparsity of cores and the tensor network structure: https://arxiv.org/abs/1912.07913
You can find more recent stuff here: https://anthony-nouy.github.io/publications.html

And he has a python lib implementing this, though I don't know how well maintained: https://anthony-nouy.github.io/tensap/

Might be helpful to consider some of the ideas or features for itensor NA.

Start by reviewing the linked papers, Anthony Nouy's publications, and the tensap library to understand which ideas may apply to ITensorNumericalAnalysis.jl. The issue does not identify files, tests, a specific feature, or a definition of done, so a maintainer would need to narrow the scope before implementation.

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