Exemple #1
0
    def __classcall_private__(cls, morphism_or_polys, domain=None):
        r"""
        Return the appropriate dynamical system on an affine scheme.

        TESTS::

            sage: A.<x> = AffineSpace(ZZ,1)
            sage: A1.<z> = AffineSpace(CC,1)
            sage: H = End(A1)
            sage: f2 = H([z^2+1])
            sage: f = DynamicalSystem_affine(f2, A)
            sage: f.domain() is A
            False

        ::

            sage: P1.<x,y> = ProjectiveSpace(QQ,1)
            sage: DynamicalSystem_affine([y, 2*x], domain=P1)
            Traceback (most recent call last):
            ...
            ValueError: "domain" must be an affine scheme
            sage: H = End(P1)
            sage: DynamicalSystem_affine(H([y, 2*x]))
            Traceback (most recent call last):
            ...
            ValueError: "domain" must be an affine scheme

        ::

            sage: R.<x,y,z> = QQ[]
            sage: f = DynamicalSystem_affine([x+y+z, y*z])
            Traceback (most recent call last):
            ...
            ValueError: Number of polys does not match dimension of Affine Space of dimension 3 over Rational Field

        ::
            sage: A.<x,y> = AffineSpace(QQ,2)
            sage: f = DynamicalSystem_affine([CC.0*x^2, y^2], domain=A)
            Traceback (most recent call last):
            ...
            TypeError: coefficients of polynomial not in Rational Field
        """
        if isinstance(morphism_or_polys, SchemeMorphism_polynomial):
            morphism = morphism_or_polys
            R = morphism.base_ring()
            polys = list(morphism)
            domain = morphism.domain()
            if not is_AffineSpace(domain) and not isinstance(
                    domain, AlgebraicScheme_subscheme_affine):
                raise ValueError('"domain" must be an affine scheme')
            if domain != morphism_or_polys.codomain():
                raise ValueError('domain and codomain do not agree')
            if R not in Fields():
                return typecall(cls, polys, domain)
            if is_FiniteField(R):
                return DynamicalSystem_affine_finite_field(polys, domain)
            return DynamicalSystem_affine_field(polys, domain)
        elif isinstance(morphism_or_polys, (list, tuple)):
            polys = list(morphism_or_polys)
        else:
            polys = [morphism_or_polys]

        PR = get_coercion_model().common_parent(*polys)
        fraction_field = any(is_FractionField(poly.parent()) for poly in polys)
        if fraction_field:
            K = PR.base_ring().fraction_field()
            # Replace base ring with its fraction field
            PR = PR.ring().change_ring(K).fraction_field()
            polys = [PR(poly) for poly in polys]
        else:
            quotient_ring = any(
                is_QuotientRing(poly.parent()) for poly in polys)
            # If any of the list entries lies in a quotient ring, we try
            # to lift all entries to a common polynomial ring.
            if quotient_ring:
                polys = [PR(poly).lift() for poly in polys]
            else:
                polys = [PR(poly) for poly in polys]
        if domain is None:
            if PR is SR:
                raise TypeError("Symbolic Ring cannot be the base ring")
            if fraction_field:
                PR = PR.ring()
            domain = AffineSpace(PR)
        else:
            # Check if we can coerce the given polynomials over the given domain
            PR = domain.ambient_space().coordinate_ring()
            try:
                if fraction_field:
                    PR = PR.fraction_field()
                polys = [PR(poly) for poly in polys]
            except TypeError:
                raise TypeError('coefficients of polynomial not in {}'.format(
                    domain.base_ring()))
        if len(polys) != domain.ambient_space().coordinate_ring().ngens():
            raise ValueError(
                'Number of polys does not match dimension of {}'.format(
                    domain))
        R = domain.base_ring()
        if R is SR:
            raise TypeError("Symbolic Ring cannot be the base ring")
        if not is_AffineSpace(domain) and not isinstance(
                domain, AlgebraicScheme_subscheme_affine):
            raise ValueError('"domain" must be an affine scheme')

        if R not in Fields():
            return typecall(cls, polys, domain)
        if is_FiniteField(R):
            return DynamicalSystem_affine_finite_field(polys, domain)
        return DynamicalSystem_affine_field(polys, domain)
Exemple #2
0
    def __classcall_private__(cls, morphism_or_polys, domain=None):
        r"""
        Return the appropriate dynamical system on an affine scheme.

        TESTS::

            sage: A.<x> = AffineSpace(ZZ,1)
            sage: A1.<z> = AffineSpace(CC,1)
            sage: H = End(A1)
            sage: f2 = H([z^2+1])
            sage: f = DynamicalSystem_affine(f2, A)
            sage: f.domain() is A
            False

        ::

            sage: P1.<x,y> = ProjectiveSpace(QQ,1)
            sage: DynamicalSystem_affine([y, 2*x], domain=P1)
            Traceback (most recent call last):
            ...
            ValueError: "domain" must be an affine scheme
            sage: H = End(P1)
            sage: DynamicalSystem_affine(H([y, 2*x]))
            Traceback (most recent call last):
            ...
            ValueError: "domain" must be an affine scheme
        """
        if isinstance(morphism_or_polys, SchemeMorphism_polynomial):
            morphism = morphism_or_polys
            R = morphism.base_ring()
            polys = list(morphism)
            domain = morphism.domain()
            if not is_AffineSpace(domain) and not isinstance(
                    domain, AlgebraicScheme_subscheme_affine):
                raise ValueError('"domain" must be an affine scheme')
            if domain != morphism_or_polys.codomain():
                raise ValueError('domain and codomain do not agree')
            if R not in Fields():
                return typecall(cls, polys, domain)
            if is_FiniteField(R):
                return DynamicalSystem_affine_finite_field(polys, domain)
            return DynamicalSystem_affine_field(polys, domain)
        elif isinstance(morphism_or_polys, (list, tuple)):
            polys = list(morphism_or_polys)
        else:
            polys = [morphism_or_polys]

        # We now arrange for all of our list entries to lie in the same ring
        # Fraction field case first
        fraction_field = False
        for poly in polys:
            P = poly.parent()
            if is_FractionField(P):
                fraction_field = True
                break
        if fraction_field:
            K = P.base_ring().fraction_field()
            # Replace base ring with its fraction field
            P = P.ring().change_ring(K).fraction_field()
            polys = [P(poly) for poly in polys]
        else:
            # If any of the list entries lies in a quotient ring, we try
            # to lift all entries to a common polynomial ring.
            quotient_ring = False
            for poly in polys:
                P = poly.parent()
                if is_QuotientRing(P):
                    quotient_ring = True
                    break
            if quotient_ring:
                polys = [P(poly).lift() for poly in polys]
            else:
                poly_ring = False
                for poly in polys:
                    P = poly.parent()
                    if is_PolynomialRing(P) or is_MPolynomialRing(P):
                        poly_ring = True
                        break
                if poly_ring:
                    polys = [P(poly) for poly in polys]

        if domain is None:
            f = polys[0]
            CR = f.parent()
            if CR is SR:
                raise TypeError("Symbolic Ring cannot be the base ring")
            if fraction_field:
                CR = CR.ring()
            domain = AffineSpace(CR)

        R = domain.base_ring()
        if R is SR:
            raise TypeError("Symbolic Ring cannot be the base ring")
        if not is_AffineSpace(domain) and not isinstance(
                domain, AlgebraicScheme_subscheme_affine):
            raise ValueError('"domain" must be an affine scheme')

        if R not in Fields():
            return typecall(cls, polys, domain)
        if is_FiniteField(R):
            return DynamicalSystem_affine_finite_field(polys, domain)
        return DynamicalSystem_affine_field(polys, domain)
Exemple #3
0
    def __classcall_private__(cls, morphism_or_polys, domain=None):
        r"""
        Return the appropriate dynamical system on an affine scheme.

        TESTS::

            sage: A.<x> = AffineSpace(ZZ,1)
            sage: A1.<z> = AffineSpace(CC,1)
            sage: H = End(A1)
            sage: f2 = H([z^2+1])
            sage: f = DynamicalSystem_affine(f2, A)
            sage: f.domain() is A
            False

        ::

            sage: P1.<x,y> = ProjectiveSpace(QQ,1)
            sage: DynamicalSystem_affine([y, 2*x], domain=P1)
            Traceback (most recent call last):
            ...
            ValueError: "domain" must be an affine scheme
            sage: H = End(P1)
            sage: DynamicalSystem_affine(H([y, 2*x]))
            Traceback (most recent call last):
            ...
            ValueError: "domain" must be an affine scheme
        """
        if isinstance(morphism_or_polys, SchemeMorphism_polynomial):
            morphism = morphism_or_polys
            R = morphism.base_ring()
            polys = list(morphism)
            domain = morphism.domain()
            if not is_AffineSpace(domain) and not isinstance(domain, AlgebraicScheme_subscheme_affine):
                raise ValueError('"domain" must be an affine scheme')
            if domain != morphism_or_polys.codomain():
                raise ValueError('domain and codomain do not agree')
            if R not in Fields():
                return typecall(cls, polys, domain)
            if is_FiniteField(R):
                return DynamicalSystem_affine_finite_field(polys, domain)
            return DynamicalSystem_affine_field(polys, domain)
        elif isinstance(morphism_or_polys,(list, tuple)):
            polys = list(morphism_or_polys)
        else:
            polys = [morphism_or_polys]

        # We now arrange for all of our list entries to lie in the same ring
        # Fraction field case first
        fraction_field = False
        for poly in polys:
            P = poly.parent()
            if is_FractionField(P):
                fraction_field = True
                break
        if fraction_field:
            K = P.base_ring().fraction_field()
            # Replace base ring with its fraction field
            P = P.ring().change_ring(K).fraction_field()
            polys = [P(poly) for poly in polys]
        else:
            # If any of the list entries lies in a quotient ring, we try
            # to lift all entries to a common polynomial ring.
            quotient_ring = False
            for poly in polys:
                P = poly.parent()
                if is_QuotientRing(P):
                    quotient_ring = True
                    break
            if quotient_ring:
                polys = [P(poly).lift() for poly in polys]
            else:
                poly_ring = False
                for poly in polys:
                    P = poly.parent()
                    if is_PolynomialRing(P) or is_MPolynomialRing(P):
                        poly_ring = True
                        break
                if poly_ring:
                    polys = [P(poly) for poly in polys]

        if domain is None:
            f = polys[0]
            CR = f.parent()
            if CR is SR:
                raise TypeError("Symbolic Ring cannot be the base ring")
            if fraction_field:
                CR = CR.ring()
            domain = AffineSpace(CR)

        R = domain.base_ring()
        if R is SR:
            raise TypeError("Symbolic Ring cannot be the base ring")
        if not is_AffineSpace(domain) and not isinstance(domain, AlgebraicScheme_subscheme_affine):
            raise ValueError('"domain" must be an affine scheme')

        if R not in Fields():
            return typecall(cls, polys, domain)
        if is_FiniteField(R):
                return DynamicalSystem_affine_finite_field(polys, domain)
        return DynamicalSystem_affine_field(polys, domain)
Exemple #4
0
    def __classcall_private__(cls, morphism_or_polys, domain=None):
        r"""
        Return the appropriate dynamical system on an affine scheme.

        TESTS::

            sage: A.<x> = AffineSpace(ZZ,1)
            sage: A1.<z> = AffineSpace(CC,1)
            sage: H = End(A1)
            sage: f2 = H([z^2+1])
            sage: f = DynamicalSystem_affine(f2, A)
            sage: f.domain() is A
            False

        ::

            sage: P1.<x,y> = ProjectiveSpace(QQ,1)
            sage: DynamicalSystem_affine([y, 2*x], domain=P1)
            Traceback (most recent call last):
            ...
            ValueError: "domain" must be an affine scheme
            sage: H = End(P1)
            sage: DynamicalSystem_affine(H([y, 2*x]))
            Traceback (most recent call last):
            ...
            ValueError: "domain" must be an affine scheme

        ::

            sage: R.<x,y,z> = QQ[]
            sage: f = DynamicalSystem_affine([x+y+z, y*z])
            Traceback (most recent call last):
            ...
            ValueError: Number of polys does not match dimension of Affine Space of dimension 3 over Rational Field

        ::
            sage: A.<x,y> = AffineSpace(QQ,2)
            sage: f = DynamicalSystem_affine([CC.0*x^2, y^2], domain=A)
            Traceback (most recent call last):
            ...
            TypeError: coefficients of polynomial not in Rational Field
        """
        if isinstance(morphism_or_polys, SchemeMorphism_polynomial):
            morphism = morphism_or_polys
            R = morphism.base_ring()
            polys = list(morphism)
            domain = morphism.domain()
            if not is_AffineSpace(domain) and not isinstance(domain, AlgebraicScheme_subscheme_affine):
                raise ValueError('"domain" must be an affine scheme')
            if domain != morphism_or_polys.codomain():
                raise ValueError('domain and codomain do not agree')
            if R not in Fields():
                return typecall(cls, polys, domain)
            if is_FiniteField(R):
                return DynamicalSystem_affine_finite_field(polys, domain)
            return DynamicalSystem_affine_field(polys, domain)
        elif isinstance(morphism_or_polys,(list, tuple)):
            polys = list(morphism_or_polys)
        else:
            polys = [morphism_or_polys]

        PR = get_coercion_model().common_parent(*polys)         
        fraction_field = any(is_FractionField(poly.parent()) for poly in polys)
        if fraction_field:
            K = PR.base_ring().fraction_field()
            # Replace base ring with its fraction field
            PR = PR.ring().change_ring(K).fraction_field()
            polys = [PR(poly) for poly in polys]
        else:
            quotient_ring = any(is_QuotientRing(poly.parent()) for poly in polys)
            # If any of the list entries lies in a quotient ring, we try
            # to lift all entries to a common polynomial ring.
            if quotient_ring:
                polys = [PR(poly).lift() for poly in polys]
            else:
                polys = [PR(poly) for poly in polys]
        if domain is None:
            if PR is SR:
                raise TypeError("Symbolic Ring cannot be the base ring")
            if fraction_field:
                PR = PR.ring()
            domain = AffineSpace(PR)
        else:
            # Check if we can coerce the given polynomials over the given domain 
            PR = domain.ambient_space().coordinate_ring()
            try:
                if fraction_field:
                    PR = PR.fraction_field()
                polys = [PR(poly) for poly in polys]
            except TypeError:
                raise TypeError('coefficients of polynomial not in {}'.format(domain.base_ring()))
        if len(polys) != domain.ambient_space().coordinate_ring().ngens():
            raise ValueError('Number of polys does not match dimension of {}'.format(domain))
        R = domain.base_ring()
        if R is SR:
            raise TypeError("Symbolic Ring cannot be the base ring")
        if not is_AffineSpace(domain) and not isinstance(domain, AlgebraicScheme_subscheme_affine):
            raise ValueError('"domain" must be an affine scheme')

        if R not in Fields():
            return typecall(cls, polys, domain)
        if is_FiniteField(R):
                return DynamicalSystem_affine_finite_field(polys, domain)
        return DynamicalSystem_affine_field(polys, domain)