当前位置: 首页>>代码示例>>Python>>正文


Python Poly.atoms方法代码示例

本文整理汇总了Python中sympy.polys.Poly.atoms方法的典型用法代码示例。如果您正苦于以下问题:Python Poly.atoms方法的具体用法?Python Poly.atoms怎么用?Python Poly.atoms使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在sympy.polys.Poly的用法示例。


在下文中一共展示了Poly.atoms方法的2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: ratint

# 需要导入模块: from sympy.polys import Poly [as 别名]
# 或者: from sympy.polys.Poly import atoms [as 别名]
def ratint(f, x, **flags):
    """Performs indefinite integration of rational functions.

       Given a field :math:`K` and a rational function :math:`f = p/q`,
       where :math:`p` and :math:`q` are polynomials in :math:`K[x]`,
       returns a function :math:`g` such that :math:`f = g'`.

       >>> from sympy.integrals.rationaltools import ratint
       >>> from sympy.abc import x

       >>> ratint(36/(x**5 - 2*x**4 - 2*x**3 + 4*x**2 + x - 2), x)
       (12*x + 6)/(x**2 - 1) + 4*log(x - 2) - 4*log(x + 1)

       References
       ==========

       .. [Bro05] M. Bronstein, Symbolic Integration I: Transcendental
          Functions, Second Edition, Springer-Verlag, 2005, pp. 35-70

       See Also
       ========

       sympy.integrals.integrals.Integral.doit
       ratint_logpart, ratint_ratpart
    """
    if type(f) is not tuple:
        p, q = f.as_numer_denom()
    else:
        p, q = f

    p, q = Poly(p, x, composite=False, field=True), Poly(q, x, composite=False, field=True)

    coeff, p, q = p.cancel(q)
    poly, p = p.div(q)

    result = poly.integrate(x).as_expr()

    if p.is_zero:
        return coeff*result

    g, h = ratint_ratpart(p, q, x)

    P, Q = h.as_numer_denom()

    P = Poly(P, x)
    Q = Poly(Q, x)

    q, r = P.div(Q)

    result += g + q.integrate(x).as_expr()

    if not r.is_zero:
        symbol = flags.get('symbol', 't')

        if not isinstance(symbol, Symbol):
            t = Dummy(symbol)
        else:
            t = symbol.as_dummy()

        L = ratint_logpart(r, Q, x, t)

        real = flags.get('real')

        if real is None:
            if type(f) is not tuple:
                atoms = f.atoms()
            else:
                p, q = f

                atoms = p.atoms() | q.atoms()

            for elt in atoms - set([x]):
                if not elt.is_real:
                    real = False
                    break
            else:
                real = True

        eps = S(0)

        if not real:
            for h, q in L:
                eps += RootSum(
                    q, Lambda(t, t*log(h.as_expr())), quadratic=True)
        else:
            for h, q in L:
                R = log_to_real(h, q, x, t)

                if R is not None:
                    eps += R
                else:
                    eps += RootSum(
                        q, Lambda(t, t*log(h.as_expr())), quadratic=True)

        result += eps

    return coeff*result
开发者ID:AALEKH,项目名称:sympy,代码行数:99,代码来源:rationaltools.py

示例2: ratint

# 需要导入模块: from sympy.polys import Poly [as 别名]
# 或者: from sympy.polys.Poly import atoms [as 别名]
def ratint(f, x, **flags):
    """Performs indefinite integration of rational functions.

       Given a field K and a rational function f = p/q, where p and q
       are polynomials in K[x], returns a function g such that f = g'.

       >>> from sympy.integrals.rationaltools import ratint
       >>> from sympy.abc import x

       >>> ratint(36/(x**5 - 2*x**4 - 2*x**3 + 4*x**2 + x - 2), x)
       -4*log(1 + x) + 4*log(-2 + x) - (6 + 12*x)/(1 - x**2)

       References
       ==========

       .. [Bro05] M. Bronstein, Symbolic Integration I: Transcendental
          Functions, Second Edition, Springer-Verlag, 2005, pp. 35-70

    """
    if type(f) is not tuple:
        p, q = f.as_numer_denom()
    else:
        p, q = f

    p, q = Poly(p, x), Poly(q, x)

    c, p, q = p.cancel(q)
    poly, p = p.div(q)

    poly = poly.to_field()

    result = c*poly.integrate(x).as_basic()

    if p.is_zero:
        return result

    g, h = ratint_ratpart(p, q, x)

    P, Q = h.as_numer_denom()

    P = Poly(P, x)
    Q = Poly(Q, x)

    q, r = P.div(Q)

    result += g + q.integrate(x).as_basic()

    if not r.is_zero:
        symbol = flags.get('symbol', 't')

        if not isinstance(symbol, Symbol):
            t = Dummy(symbol)
        else:
            t = symbol

        L = ratint_logpart(r, Q, x, t)

        real = flags.get('real')

        if real is None:
            if type(f) is not tuple:
                atoms = f.atoms()
            else:
                p, q = f

                atoms = p.atoms() \
                      | q.atoms()

            for elt in atoms - set([x]):
                if not elt.is_real:
                    real = False
                    break
            else:
                real = True

        eps = S(0)

        if not real:
            for h, q in L:
                eps += RootSum(Lambda(t, t*log(h.as_basic())), q)
        else:
            for h, q in L:
                R = log_to_real(h, q, x, t)

                if R is not None:
                    eps += R
                else:
                    eps += RootSum(Lambda(t, t*log(h.as_basic())), q)

        result += eps

    return result
开发者ID:Aang,项目名称:sympy,代码行数:94,代码来源:rationaltools.py


注:本文中的sympy.polys.Poly.atoms方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。