pub fn lll_reduce_bigint_fp(basis: &[Vec<BigInt>]) -> Vec<Vec<BigInt>>Expand description
The L² lattice reduction (fpLLL): LLL with a BigFloat Gram–Schmidt — fast like floating point, but
with FP_PREC bits of precision so it survives the high dynamic range of Coppersmith/Boneh–Durfee
lattices where f64 fails, and without the determinant blow-up of the exact integer LLL. The basis
stays exact integer; only the steering is in BigFloat, and swaps update the Gram–Schmidt incrementally
(O(n³) overall rather than the O(n⁵) of recompute-on-swap).