simplify.py 文件源码

def _unpolarify(eq, exponents_only, pause=False):
    from sympy import polar_lift, exp, principal_branch, pi

    if isinstance(eq, bool) or eq.is_Atom:
        return eq

    if not pause:
        if eq.func is exp_polar:
            return exp(_unpolarify(eq.exp, exponents_only))
        if eq.func is principal_branch and eq.args[1] == 2*pi:
            return _unpolarify(eq.args[0], exponents_only)
        if (
            eq.is_Add or eq.is_Mul or eq.is_Boolean or
            eq.is_Relational and (
                eq.rel_op in ('==', '!=') and 0 in eq.args or
                eq.rel_op not in ('==', '!='))
        ):
            return eq.func(*[_unpolarify(x, exponents_only) for x in eq.args])
        if eq.func is polar_lift:
            return _unpolarify(eq.args[0], exponents_only)

    if eq.is_Pow:
        expo = _unpolarify(eq.exp, exponents_only)
        base = _unpolarify(eq.base, exponents_only,
            not (expo.is_integer and not pause))
        return base**expo

    if eq.is_Function and getattr(eq.func, 'unbranched', False):
        return eq.func(*[_unpolarify(x, exponents_only, exponents_only)
            for x in eq.args])

    return eq.func(*[_unpolarify(x, exponents_only, True) for x in eq.args])