Fix full_update for tensors with dangling indices#4
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Full update now handles site tensors that carry a dangling index the gate does not act on, such as the length-1 auxiliary index that makes a definite-charge tensor symmetry-invariant. Previously `optimise_p_q`'s right-hand-side closure `b` built the bra as `conj(prime(r))` and un-primed the whole contraction with `noprime`. A dangling index the gate leaves untouched then survived both unprimed (ket) and primed (bra) and collapsed to a duplicate name under `noprime`, throwing `Dimension names must be distinct`. The fix un-primes those spectator legs on the bra so they trace against the ket, mirroring what the metric closure `M_p` already did. Tensors without dangling indices are unchanged, so the dense backend is unaffected. A separate numerical discrepancy remains on the GradedArrays backend (the TensorKit backend gives correct results). It does not come from this factorization logic and is being looked into separately.
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Summary
Full update now handles site tensors that carry a dangling index the gate does not act on, such as the length-1 auxiliary index that makes a definite-charge tensor symmetry-invariant. Previously
optimise_p_q's right-hand-side closurebbuilt the bra asconj(prime(r))and un-primed the whole contraction withnoprime. A dangling index the gate leaves untouched then survived both unprimed (ket) and primed (bra) and collapsed to a duplicate name undernoprime, throwingDimension names must be distinct. The fix un-primes those spectator legs on the bra so they trace against the ket, mirroring what the metric closureM_palready did. Tensors without dangling indices are unchanged, so the dense backend is unaffected.This bumps the
ITensorBasefloor to0.11.3, where an emptyreplaceindsis a no-op, so the spectator un-priming applies unconditionally with no special case for tensors that have no dangling index.A separate numerical discrepancy remains on the GradedArrays backend (the TensorKit backend gives correct results). It does not come from this factorization logic and is being looked into separately.