I tried a (not intentionally) silly combination of conserved charges: ITensors.siteind("Fermion", conserve_nf=true, conserve_nfparity=true) I would expect this to result in two conserved charges (Nf, NfParity), but I get only Nf. While sensible as parity is redundant (so maybe should be left as i…

Sounds good – I just made a PR which will add a warning: https://github.com/ITensor/ITensors.jl/pull/1662

Hi Matan, Thanks for sharing this. I can see why it’s surprising. We set the behavior that way since conserving number does also implicitly conserve parity, so you get the desired behavior that way in a kind of “zoomed out” sense. What would you suggest should be the behavior here? I could see a g…

Unexpected qns for fermionic siteind

ITensor Julia Questions

matanlotem July 27, 2025, 7:45pm 3

I agree, I think an error, or maybe even a warning, would be sufficient.

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Unexpected qns for fermionic siteind

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