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这是来自 Microsoft SEAL-3.4 库的 seal / keygenerator.h 中对 GaloisKey 的描述：

/**
    Generates and returns Galois keys. This function creates specific Galois
    keys that can be used to apply specific Galois automorphisms on encrypted
    data. The user needs to give as input a vector of Galois elements
    corresponding to the keys that are to be created.

    The Galois elements are odd integers in the interval [1, M-1], where
    M = 2*N, and N = poly_modulus_degree. Used with batching, a Galois element
    3^i % M corresponds to a cyclic row rotation i steps to the left, and
    a Galois element 3^(N/2-i) % M corresponds to a cyclic row rotation i
    steps to the right. The Galois element M-1 corresponds to a column rotation
    (row swap) in BFV, and complex conjugation in CKKS. In the polynomial view
    (not batching), a Galois automorphism by a Galois element p changes
    Enc(plain(x)) to Enc(plain(x^p)).

    @param[in] galois_elts The Galois elements for which to generate keys
    @throws std::logic_error if the encryption parameters do not support
    batching and scheme is scheme_type::BFV
    @throws std::logic_error if the encryption parameters do not support
    keyswitching
    @throws std::invalid_argument if the Galois elements are not valid
    */
    SEAL_NODISCARD inline GaloisKeys galois_keys(
        const std::vector<std::uint64_t> &galois_elts)
    {
        return galois_keys(galois_elts, false);
    }

如何为 GaloisKey 创建更好的 Galois 元素。

一般来说：

GaloisKey gal_keys = keygen.galois_keys();

但是密文第一次旋转是正确的，第二次旋转是错误的。

具体的错误是，比如我的一个密文是[0.0001,0.0001, ... 0.0001]，旋转后解密为[1.0000,1.2000,1.7000 ...]

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