Пример #1
0
    def __init__(self, parent, polynomial, check=True):
        """
        Create an element of the quotient of a polynomial ring.

        INPUT:


        -  ``parent`` - a quotient of a polynomial ring

        -  ``polynomial`` - a polynomial

        -  ``check`` - bool (optional): whether or not to
           verify that x is a valid element of the polynomial ring and reduced
           (mod the modulus).
        """
        from sage.rings.polynomial.polynomial_quotient_ring import PolynomialQuotientRing_generic
        from sage.rings.polynomial.polynomial_element import Polynomial

        CommutativeRingElement.__init__(self, parent)
        if check:
            if not isinstance(parent, PolynomialQuotientRing_generic):
                raise TypeError("parent must be a polynomial quotient ring")

            if not isinstance(polynomial, Polynomial):
                raise TypeError("polynomial must be a polynomial")

            if not polynomial in parent.polynomial_ring():
                raise TypeError(
                    "polynomial must be in the polynomial ring of the parent")

        f = parent.modulus()
        if polynomial.degree() >= f.degree() and polynomial.degree() >= 0:
            try:
                polynomial %= f
            except AttributeError:
                A = polynomial
                B = f
                R = A
                P = B.parent()
                Q = P(0)
                X = P.gen()
                while R.degree() >= B.degree():
                    S = P((R.leading_coefficient() / B.leading_coefficient()
                           )) * X**(R.degree() - B.degree())
                    Q = Q + S
                    R = R - S * B
                polynomial = R
        self._polynomial = polynomial
    def __init__(self, parent, polynomial, check=True):
        """
        Create an element of the quotient of a polynomial ring.

        INPUT:


        -  ``parent`` - a quotient of a polynomial ring

        -  ``polynomial`` - a polynomial

        -  ``check`` - bool (optional): whether or not to
           verify that x is a valid element of the polynomial ring and reduced
           (mod the modulus).
        """
        from sage.rings.polynomial.polynomial_quotient_ring import PolynomialQuotientRing_generic
        from sage.rings.polynomial.polynomial_element import Polynomial

        CommutativeRingElement.__init__(self, parent)
        if check:
            if not isinstance(parent, PolynomialQuotientRing_generic):
                raise TypeError("parent must be a polynomial quotient ring")

            if not isinstance(polynomial, Polynomial):
                raise TypeError("polynomial must be a polynomial")

            if not polynomial in parent.polynomial_ring():
                raise TypeError("polynomial must be in the polynomial ring of the parent")

        f = parent.modulus()
        if polynomial.degree() >= f.degree() and polynomial.degree() >= 0:
            try:
                polynomial %= f
            except AttributeError:
                A = polynomial
                B = f
                R = A
                P = B.parent()
                Q = P(0)
                X = P.gen()
                while R.degree() >= B.degree():
                    S = P((R.leading_coefficient()/B.leading_coefficient())) * X**(R.degree()-B.degree())
                    Q = Q + S
                    R = R - S*B
                polynomial = R
        self._polynomial = polynomial