def dup_zz_hensel_lift(p, f, f_list, l, K): """ Multifactor Hensel lifting in `Z[x]`. Given a prime `p`, polynomial `f` over `Z[x]` such that `lc(f)` is a unit modulo `p`, monic pair-wise coprime polynomials `f_i` over `Z[x]` satisfying:: f = lc(f) f_1 ... f_r (mod p) and a positive integer `l`, returns a list of monic polynomials `F_1`, `F_2`, ..., `F_r` satisfying:: f = lc(f) F_1 ... F_r (mod p**l) F_i = f_i (mod p), i = 1..r References ========== 1. [Gathen99]_ """ r = len(f_list) lc = dup_LC(f, K) if r == 1: F = dup_mul_ground(f, K.gcdex(lc, p**l)[0], K) return [dup_trunc(F, p**l, K)] m = p k = r // 2 d = int(_ceil(_log(l, 2))) g = gf_from_int_poly([lc], p) for f_i in f_list[:k]: g = gf_mul(g, gf_from_int_poly(f_i, p), p, K) h = gf_from_int_poly(f_list[k], p) for f_i in f_list[k + 1:]: h = gf_mul(h, gf_from_int_poly(f_i, p), p, K) s, t, _ = gf_gcdex(g, h, p, K) g = gf_to_int_poly(g, p) h = gf_to_int_poly(h, p) s = gf_to_int_poly(s, p) t = gf_to_int_poly(t, p) for _ in range(1, d + 1): (g, h, s, t), m = dup_zz_hensel_step(m, f, g, h, s, t, K), m**2 return dup_zz_hensel_lift(p, g, f_list[:k], l, K) \ + dup_zz_hensel_lift(p, h, f_list[k:], l, K)
def dup_zz_hensel_lift(p, f, f_list, l, K): """ Multifactor Hensel lifting in `Z[x]`. Given a prime `p`, polynomial `f` over `Z[x]` such that `lc(f)` is a unit modulo `p`, monic pair-wise coprime polynomials `f_i` over `Z[x]` satisfying:: f = lc(f) f_1 ... f_r (mod p) and a positive integer `l`, returns a list of monic polynomials `F_1`, `F_2`, ..., `F_r` satisfying:: f = lc(f) F_1 ... F_r (mod p**l) F_i = f_i (mod p), i = 1..r References ========== 1. [Gathen99]_ """ r = len(f_list) lc = dup_LC(f, K) if r == 1: F = dup_mul_ground(f, K.gcdex(lc, p**l)[0], K) return [ dup_trunc(F, p**l, K) ] m = p k = r // 2 d = int(_ceil(_log(l, 2))) g = gf_from_int_poly([lc], p) for f_i in f_list[:k]: g = gf_mul(g, gf_from_int_poly(f_i, p), p, K) h = gf_from_int_poly(f_list[k], p) for f_i in f_list[k + 1:]: h = gf_mul(h, gf_from_int_poly(f_i, p), p, K) s, t, _ = gf_gcdex(g, h, p, K) g = gf_to_int_poly(g, p) h = gf_to_int_poly(h, p) s = gf_to_int_poly(s, p) t = gf_to_int_poly(t, p) for _ in range(1, d + 1): (g, h, s, t), m = dup_zz_hensel_step(m, f, g, h, s, t, K), m**2 return dup_zz_hensel_lift(p, g, f_list[:k], l, K) \ + dup_zz_hensel_lift(p, h, f_list[k:], l, K)
def test_gf_gcdex(): assert gf_gcdex([], [], 11, ZZ) == ([1], [], []) assert gf_gcdex([2], [], 11, ZZ) == ([6], [], [1]) assert gf_gcdex([], [2], 11, ZZ) == ([], [6], [1]) assert gf_gcdex([2], [2], 11, ZZ) == ([], [6], [1]) assert gf_gcdex([], [3,0], 11, ZZ) == ([], [4], [1,0]) assert gf_gcdex([3,0], [], 11, ZZ) == ([4], [], [1,0]) assert gf_gcdex([3,0], [3,0], 11, ZZ) == ([], [4], [1,0]) assert gf_gcdex([1,8,7], [1,7,1,7], 11, ZZ) == ([5,6], [6], [1,7])
def inverse(f): # Fast inverse method global phid global q p = ZZ.map(f) mod = ZZ.map(phid) s, t, g = gf_gcdex(p, mod, q, ZZ) if len(g) == 1 and g[0] == 1: return s else: return [-1]
def find_inv(poly, mod, constant = -a): xN_minus_a = np.zeros(N+1) xN_minus_a[0] = 1 xN_minus_a[-1] = constant f_poly = ZZ.map(poly) x_mod = ZZ.map(xN_minus_a) s, t, g = gf_gcdex(f_poly, x_mod, mod, ZZ) # Recall that s*f + t*g = h. # If g = 1, then s is the inverse of f mod t (= x^n-a) if len(g) == 1 and g[0] == 1: return trunc_polynomial(s) return trunc_polynomial(0)
def dup_zz_diophantine(F, m, p, K): """Wang/EEZ: Solve univariate Diophantine equations. """ if len(F) == 2: a, b = F f = gf_from_int_poly(a, p) g = gf_from_int_poly(b, p) s, t, G = gf_gcdex(g, f, p, K) s = gf_lshift(s, m, K) t = gf_lshift(t, m, K) q, s = gf_div(s, f, p, K) t = gf_add_mul(t, q, g, p, K) s = gf_to_int_poly(s, p) t = gf_to_int_poly(t, p) result = [s, t] else: G = [F[-1]] for f in reversed(F[1:-1]): G.insert(0, dup_mul(f, G[0], K)) S, T = [], [[1]] for f, g in zip(F, G): t, s = dmp_zz_diophantine([g, f], T[-1], [], 0, p, 1, K) T.append(t) S.append(s) result, S = [], S + [T[-1]] for s, f in zip(S, F): s = gf_from_int_poly(s, p) f = gf_from_int_poly(f, p) r = gf_rem(gf_lshift(s, m, K), f, p, K) s = gf_to_int_poly(r, p) result.append(s) return result
def test_gf_euclidean(): assert gf_gcd([], [], 11, ZZ) == [] assert gf_gcd([2], [], 11, ZZ) == [1] assert gf_gcd([], [2], 11, ZZ) == [1] assert gf_gcd([2], [2], 11, ZZ) == [1] assert gf_gcd([], [1, 0], 11, ZZ) == [1, 0] assert gf_gcd([1, 0], [], 11, ZZ) == [1, 0] assert gf_gcd([3, 0], [3, 0], 11, ZZ) == [1, 0] assert gf_gcd([1, 8, 7], [1, 7, 1, 7], 11, ZZ) == [1, 7] assert gf_gcdex([], [], 11, ZZ) == ([1], [], []) assert gf_gcdex([2], [], 11, ZZ) == ([6], [], [1]) assert gf_gcdex([], [2], 11, ZZ) == ([], [6], [1]) assert gf_gcdex([2], [2], 11, ZZ) == ([], [6], [1]) assert gf_gcdex([], [3, 0], 11, ZZ) == ([], [4], [1, 0]) assert gf_gcdex([3, 0], [], 11, ZZ) == ([4], [], [1, 0]) assert gf_gcdex([3, 0], [3, 0], 11, ZZ) == ([], [4], [1, 0]) assert gf_gcdex([1, 8, 7], [1, 7, 1, 7], 11, ZZ) == ([5, 6], [6], [1, 7])
def test_gf_euclidean(): assert gf_gcd([], [], 11, ZZ) == [] assert gf_gcd([2], [], 11, ZZ) == [1] assert gf_gcd([], [2], 11, ZZ) == [1] assert gf_gcd([2], [2], 11, ZZ) == [1] assert gf_gcd([], [1,0], 11, ZZ) == [1,0] assert gf_gcd([1,0], [], 11, ZZ) == [1,0] assert gf_gcd([3,0], [3,0], 11, ZZ) == [1,0] assert gf_gcd([1,8,7], [1,7,1,7], 11, ZZ) == [1,7] assert gf_gcdex([], [], 11, ZZ) == ([1], [], []) assert gf_gcdex([2], [], 11, ZZ) == ([6], [], [1]) assert gf_gcdex([], [2], 11, ZZ) == ([], [6], [1]) assert gf_gcdex([2], [2], 11, ZZ) == ([], [6], [1]) assert gf_gcdex([], [3,0], 11, ZZ) == ([], [4], [1,0]) assert gf_gcdex([3,0], [], 11, ZZ) == ([4], [], [1,0]) assert gf_gcdex([3,0], [3,0], 11, ZZ) == ([], [4], [1,0]) assert gf_gcdex([1,8,7], [1,7,1,7], 11, ZZ) == ([5,6], [6], [1,7])
def inv(self, x): s, t, h = gf_gcdex(x, self.reducing, self.p, ZZ) return s
def gf_inv(p1,p2,m): res = gf_gcdex(gf_strip(p2), p1, m, ZZ) if res[2] != [1]: print("Nie ma odwrotnego") return res[0]
def gf_inv(a): # irriducible polynomial # mod = 0x18f57 => x^16 + x^15 + x^11 + x^10 + x^9 + x^8 + x^6 + x^4 + x^2 + x^1 + 1 Polynome irreductible mod = [1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1] a = hextolist(a) s, t, g = gf_gcdex(ZZ.map(gf_strip(a)), ZZ.map(mod), 2, ZZ) return listtohex(s)
def inv(self, x: list) -> list: s, t, h = gf_gcdex(x, self.reducing, self.p, ZZ) return s