(f, g, u, K)
Compute ``f**(-1)`` mod ``x**n`` using Newton iteration.

    Examples
    ========

    >>> from sympy.polys import ring, QQ
    >>> R, x,y = ring("x,y", QQ)
Compute ``f**(-1)`` mod ``x**n`` using Newton iteration.
Compute f ** ( - 1 ) mod x ** n using Newton iteration .
def dmp_revert(f, g, u, K):
    """
    Compute ``f**(-1)`` mod ``x**n`` using Newton iteration.

    Examples
    ========

    >>> from sympy.polys import ring, QQ
    >>> R, x,y = ring("x,y", QQ)

    """
    if not u:
        return dup_revert(f, g, K)
    else:
        raise MultivariatePolynomialError(f, g)
def dmp_revert ( f , g , u , K ) : if not u : return dup_revert ( f , g , K ) else : raise MultivariatePolynomialError ( f , g )