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Python sieve.primerange函数代码示例

本文整理汇总了Python中sympy.ntheory.sieve.primerange函数的典型用法代码示例。如果您正苦于以下问题:Python primerange函数的具体用法?Python primerange怎么用?Python primerange使用的例子?那么恭喜您, 这里精选的函数代码示例或许可以为您提供帮助。


在下文中一共展示了primerange函数的8个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Python代码示例。

示例1: _swing

    def _swing(cls, n):
        if n < 33:
            return cls._small_swing[n]
        else:
            N, primes = int(_sqrt(n)), []

            for prime in sieve.primerange(3, N + 1):
                p, q = 1, n

                while True:
                    q //= prime

                    if q > 0:
                        if q & 1 == 1:
                            p *= prime
                    else:
                        break

                if p > 1:
                    primes.append(p)

            for prime in sieve.primerange(N + 1, n//3 + 1):
                if (n // prime) & 1 == 1:
                    primes.append(prime)

            L_product = R_product = 1

            for prime in sieve.primerange(n//2 + 1, n + 1):
                L_product *= prime

            for prime in primes:
                R_product *= prime

            return L_product*R_product
开发者ID:abhishekkumawat23,项目名称:sympy,代码行数:34,代码来源:factorials.py

示例2: _facmod

    def _facmod(self, n, q):
        res, N = 1, int(_sqrt(n))

        # Exponent of prime p in n! is e_p(n) = [n/p] + [n/p**2] + ...
        # for p > sqrt(n), e_p(n) < sqrt(n), the primes with [n/p] = m,
        # occur consecutively and are grouped together in pw[m] for
        # simultaneous exponentiation at a later stage
        pw = [1]*N

        m = 2 # to initialize the if condition below
        for prime in sieve.primerange(2, n + 1):
            if m > 1:
                m, y = 0, n // prime
                while y:
                    m += y
                    y //= prime
            if m < N:
                pw[m] = pw[m]*prime % q
            else:
                res = res*pow(prime, m, q) % q

        for ex, bs in enumerate(pw):
            if ex == 0 or bs == 1:
                continue
            if bs == 0:
                return 0
            res = res*pow(bs, ex, q) % q

        return res
开发者ID:KonstantinTogoi,项目名称:sympy,代码行数:29,代码来源:factorials.py

示例3: eval

    def eval(cls, n, k):
        n, k = map(sympify, (n, k))

        if k.is_Number:
            if k.is_Integer:
                if k < 0:
                    return S.Zero
                elif k == 0 or n == k:
                    return S.One
                elif n.is_Integer and n >= 0:
                    n, k = int(n), int(k)

                    if k > n:
                        return S.Zero
                    elif k > n // 2:
                        k = n - k

                    M, result = int(_sqrt(n)), 1

                    for prime in sieve.primerange(2, n+1):
                        if prime > n - k:
                            result *= prime
                        elif prime > n // 2:
                            continue
                        elif prime > M:
                            if n % prime < k % prime:
                                result *= prime
                        else:
                            N, K = n, k
                            exp = a = 0

                            while N > 0:
                                a = int((N % prime) < (K % prime + a))
                                N, K = N // prime, K // prime
                                exp = a + exp

                            if exp > 0:
                                result *= prime**exp

                    return C.Integer(result)
                else:
                    result = n - k + 1

                    for i in xrange(2, k+1):
                        result *= n-k+i
                        result /= i

                    return result
        elif k.is_negative:
            return S.Zero
        elif (n - k).simplify().is_negative:
            return S.Zero
        else:
            d = n - k

            if d.is_Integer:
                return cls.eval(n, d)
开发者ID:BDGLunde,项目名称:sympy,代码行数:57,代码来源:factorials.py

示例4: eval

    def eval(cls, r, k):
        r, k = map(sympify, (r, k))

        if k.is_Number:
            if k is S.Zero:
                return S.One
            elif k.is_Integer:
                if k.is_negative:
                    return S.Zero
                else:
                    if r.is_Integer and r.is_nonnegative:
                        r, k = int(r), int(k)

                        if k > r:
                            return S.Zero
                        elif k > r // 2:
                            k = r - k

                        M, result = int(sqrt(r)), 1

                        for prime in sieve.primerange(2, r+1):
                            if prime > r - k:
                                result *= prime
                            elif prime > r // 2:
                                continue
                            elif prime > M:
                                if r % prime < k % prime:
                                    result *= prime
                            else:
                                R, K = r, k
                                exp = a = 0

                                while R > 0:
                                    a = int((R % prime) < (K % prime + a))
                                    R, K = R // prime, K // prime
                                    exp = a + exp

                                if exp > 0:
                                    result *= prime**exp

                        return C.Integer(result)
                    else:
                        result = r - k + 1

                        for i in xrange(2, k+1):
                            result *= r-k+i
                            result /= i

                        return result

        if k.is_integer:
            if k.is_negative:
                return S.Zero
        else:
            return C.gamma(r+1)/(C.gamma(r-k+1)*C.gamma(k+1))
开发者ID:bibile,项目名称:sympy,代码行数:55,代码来源:factorials.py

示例5: _eval_apply

    def _eval_apply(cls, r, k):
        r, k = map(Basic.sympify, (r, k))

        if isinstance(k, Basic.Number):
            if isinstance(k, Basic.Zero):
                return S.One
            elif isinstance(k, Basic.Integer):
                if k.is_negative:
                    return S.Zero
                else:
                    if isinstance(r, Basic.Integer) and r.is_nonnegative:
                        r, k = int(r), int(k)

                        if k > r:
                            return S.Zero
                        elif k > r / 2:
                            k = r - k

                        M, result = int(sqrt(r)), 1

                        for prime in sieve.primerange(2, r+1):
                            if prime > r - k:
                                result *= prime
                            elif prime > r / 2:
                                continue
                            elif prime > M:
                                if r % prime < k % prime:
                                    result *= prime
                            else:
                                R, K = r, k
                                exp = a = 0

                                while R > 0:
                                    a = int((R % prime) < (K % prime + a))
                                    R, K = R / prime, K / prime
                                    exp = a + exp

                                if exp > 0:
                                    result *= prime**exp

                        return Basic.Integer(result)
                    else:
                        result = r - k + 1

                        for i in xrange(2, k+1):
                            result *= r-k+i
                            result /= i

                        return result

        if k.is_integer:
            if k.is_negative:
                return S.Zero
        else:
            return Basic.gamma(r+1)/(Basic.gamma(r-k+1)*Basic.gamma(k+1))
开发者ID:certik,项目名称:sympy-oldcore,代码行数:55,代码来源:factorials.py

示例6: _eval

    def _eval(self, n, k):
        # n.is_Number and k.is_Integer and k != 1 and n != k
        from sympy.functions.elementary.exponential import log
        from sympy.core import N

        if k.is_Integer:
            if n.is_Integer and n >= 0:
                n, k = int(n), int(k)

                if k > n:
                    return S.Zero
                elif k > n // 2:
                    k = n - k

                if HAS_GMPY:
                    from sympy.core.compatibility import gmpy
                    return Integer(gmpy.bincoef(n, k))

                prime_count_estimate = N(n / log(n))

                # if the number of primes less than n is less than k, use prime sieve method
                # otherwise it is more memory efficient to compute factorials explicitly
                if prime_count_estimate < k:
                    M, result = int(_sqrt(n)), 1
                    for prime in sieve.primerange(2, n + 1):
                        if prime > n - k:
                            result *= prime
                        elif prime > n // 2:
                            continue
                        elif prime > M:
                            if n % prime < k % prime:
                                result *= prime
                        else:
                            N, K = n, k
                            exp = a = 0

                            while N > 0:
                                a = int((N % prime) < (K % prime + a))
                                N, K = N // prime, K // prime
                                exp = a + exp

                            if exp > 0:
                                result *= prime**exp
                else:
                    result = ff(n, k) / factorial(k)
                return Integer(result)
            else:
                d = result = n - k + 1
                for i in range(2, k + 1):
                    d += 1
                    result *= d
                    result /= i
                return result
开发者ID:aprasanna,项目名称:sympy,代码行数:53,代码来源:factorials.py

示例7: _eval

    def _eval(self, n, k):
        # n.is_Number and k.is_Integer and k != 1 and n != k
        if k.is_Integer:
            if n.is_Integer and n >= 0:
                n, k = int(n), int(k)

                if k > n:
                    return S.Zero
                elif k > n // 2:
                    k = n - k

                M, result = int(_sqrt(n)), 1

                for prime in sieve.primerange(2, n + 1):
                    if prime > n - k:
                        result *= prime
                    elif prime > n // 2:
                        continue
                    elif prime > M:
                        if n % prime < k % prime:
                            result *= prime
                    else:
                        N, K = n, k
                        exp = a = 0

                        while N > 0:
                            a = int((N % prime) < (K % prime + a))
                            N, K = N // prime, K // prime
                            exp = a + exp

                        if exp > 0:
                            result *= prime**exp
                return Integer(result)
            else:
                d = result = n - k + 1
                for i in range(2, k + 1):
                    d += 1
                    result *= d
                    result /= i
                return result
开发者ID:AlexanderKulka,项目名称:sympy,代码行数:40,代码来源:factorials.py

示例8: _eval_Mod

    def _eval_Mod(self, q):
        n, k = self.args

        if not all(x.is_integer for x in (n, k, q)):
            raise ValueError("Integers expected for binomial Mod")

        if all(x.is_Integer for x in (n, k, q)):
            n, k = map(int, (n, k))
            aq, res = abs(q), 1

            # handle negative integers k or n
            if k < 0:
                return 0
            if n < 0:
                n = -n + k - 1
                res = -1 if k%2 else 1

            # non negative integers k and n
            if k > n:
                return 0

            isprime = aq.is_prime
            aq = int(aq)
            if isprime:
                if aq < n:
                    # use Lucas Theorem
                    N, K = n, k
                    while N or K:
                        res = res*binomial(N % aq, K % aq) % aq
                        N, K = N // aq, K // aq

                else:
                    # use Factorial Modulo
                    d = n - k
                    if k > d:
                        k, d = d, k
                    kf = 1
                    for i in range(2, k + 1):
                        kf = kf*i % aq
                    df = kf
                    for i in range(k + 1, d + 1):
                        df = df*i % aq
                    res *= df
                    for i in range(d + 1, n + 1):
                        res = res*i % aq

                    res *= pow(kf*df % aq, aq - 2, aq)
                    res %= aq

            else:
                # Binomial Factorization is performed by calculating the
                # exponents of primes <= n in `n! /(k! (n - k)!)`,
                # for non-negative integers n and k. As the exponent of
                # prime in n! is e_p(n) = [n/p] + [n/p**2] + ...
                # the exponent of prime in binomial(n, k) would be
                # e_p(n) - e_p(k) - e_p(n - k)
                M = int(_sqrt(n))
                for prime in sieve.primerange(2, n + 1):
                    if prime > n - k:
                        res = res*prime % aq
                    elif prime > n // 2:
                        continue
                    elif prime > M:
                        if n % prime < k % prime:
                            res = res*prime % aq
                    else:
                        N, K = n, k
                        exp = a = 0

                        while N > 0:
                            a = int((N % prime) < (K % prime + a))
                            N, K = N // prime, K // prime
                            exp += a

                        if exp > 0:
                            res *= pow(prime, exp, aq)
                            res %= aq

            return Integer(res % q)
开发者ID:KonstantinTogoi,项目名称:sympy,代码行数:79,代码来源:factorials.py


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