Exemplo n.º 1
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 def as_poly(self, x=None):
     """Create a Poly instance from ``self``. """
     if x is not None:
         return Poly.new(self.rep, x)
     else:
         if self.alias is not None:
             return Poly.new(self.rep, self.alias)
         else:
             return PurePoly.new(self.rep, Dummy('x'))
Exemplo n.º 2
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 def as_poly(self, x=None):
     """Create a Poly instance from ``self``. """
     if x is not None:
         return Poly.new(self.rep, x)
     else:
         if self.alias is not None:
             return Poly.new(self.rep, self.alias)
         else:
             return PurePoly.new(self.rep, Dummy('x'))
Exemplo n.º 3
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def gegenbauer_poly(n, a, x=None, polys=False):
    """Generates Gegenbauer polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    a
        Decides minimal domain for the list of
        coefficients.
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError(
            "can't generate Gegenbauer polynomial of degree %s" % n)

    K, a = construct_domain(a, field=True)
    poly = DMP(dup_gegenbauer(int(n), a, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 4
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def jacobi_poly(n, a, b, x=None, polys=False):
    """Generates Jacobi polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    a
        Lower limit of minimal domain for the list of
        coefficients.
    b
        Upper limit of minimal domain for the list of
        coefficients.
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError("can't generate Jacobi polynomial of degree %s" % n)

    K, v = construct_domain([a, b], field=True)
    poly = DMP(dup_jacobi(int(n), v[0], v[1], K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 5
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def laguerre_poly(n, x=None, alpha=None, polys=False):
    """Generates Laguerre polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    alpha
        Decides minimal domain for the list
        of coefficients.
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError("can't generate Laguerre polynomial of degree %s" % n)

    if alpha is not None:
        K, alpha = construct_domain(
            alpha, field=True)  # XXX: ground_field=True
    else:
        K, alpha = QQ, QQ(0)

    poly = DMP(dup_laguerre(int(n), alpha, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 6
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def chebyshevu_poly(n, x=None, polys=False):
    """Generates Chebyshev polynomial of the second kind of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError(
            "can't generate 2nd kind Chebyshev polynomial of degree %s" % n)

    poly = DMP(dup_chebyshevu(int(n), ZZ), ZZ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 7
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def jacobi_poly(n, a, b, x=None, polys=False):
    """Generates Jacobi polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    a
        Lower limit of minimal domain for the list of
        coefficients.
    b
        Upper limit of minimal domain for the list of
        coefficients.
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError("can't generate Jacobi polynomial of degree %s" % n)

    K, v = construct_domain([a, b], field=True)
    poly = DMP(dup_jacobi(int(n), v[0], v[1], K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 8
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def gegenbauer_poly(n, a, x=None, polys=False):
    """Generates Gegenbauer polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    a
        Decides minimal domain for the list of
        coefficients.
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError(
            "can't generate Gegenbauer polynomial of degree %s" % n)

    K, a = construct_domain(a, field=True)
    poly = DMP(dup_gegenbauer(int(n), a, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 9
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def chebyshevu_poly(n, x=None, polys=False):
    """Generates Chebyshev polynomial of the second kind of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError(
            "can't generate 2nd kind Chebyshev polynomial of degree %s" % n)

    poly = DMP(dup_chebyshevu(int(n), ZZ), ZZ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 10
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def laguerre_poly(n, x=None, alpha=None, polys=False):
    """Generates Laguerre polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    alpha
        Decides minimal domain for the list
        of coefficients.
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError("can't generate Laguerre polynomial of degree %s" % n)

    if alpha is not None:
        K, alpha = construct_domain(
            alpha, field=True)  # XXX: ground_field=True
    else:
        K, alpha = QQ, QQ(0)

    poly = DMP(dup_laguerre(int(n), alpha, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 11
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def legendre_poly(n, x=None, polys=False):
    """Generates Legendre polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError("Cannot generate Legendre polynomial of degree %s" %
                         n)

    poly = DMP(dup_legendre(int(n), QQ), QQ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 12
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def spherical_bessel_fn(n, x=None, polys=False):
    """
    Coefficients for the spherical Bessel functions.

    Those are only needed in the jn() function.

    The coefficients are calculated from:

    fn(0, z) = 1/z
    fn(1, z) = 1/z**2
    fn(n-1, z) + fn(n+1, z) == (2*n+1)/z * fn(n, z)

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.

    Examples
    ========

    >>> from sympy.polys.orthopolys import spherical_bessel_fn as fn
    >>> from sympy import Symbol
    >>> z = Symbol("z")
    >>> fn(1, z)
    z**(-2)
    >>> fn(2, z)
    -1/z + 3/z**3
    >>> fn(3, z)
    -6/z**2 + 15/z**4
    >>> fn(4, z)
    1/z - 45/z**3 + 105/z**5

    """

    if n < 0:
        dup = dup_spherical_bessel_fn_minus(-int(n), ZZ)
    else:
        dup = dup_spherical_bessel_fn(int(n), ZZ)

    poly = DMP(dup, ZZ)

    if x is not None:
        poly = Poly.new(poly, 1/x)
    else:
        poly = PurePoly.new(poly, 1/Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 13
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def spherical_bessel_fn(n, x=None, polys=False):
    """
    Coefficients for the spherical Bessel functions.

    Those are only needed in the jn() function.

    The coefficients are calculated from:

    fn(0, z) = 1/z
    fn(1, z) = 1/z**2
    fn(n-1, z) + fn(n+1, z) == (2*n+1)/z * fn(n, z)

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.

    Examples
    ========

    >>> from sympy.polys.orthopolys import spherical_bessel_fn as fn
    >>> from sympy import Symbol
    >>> z = Symbol("z")
    >>> fn(1, z)
    z**(-2)
    >>> fn(2, z)
    -1/z + 3/z**3
    >>> fn(3, z)
    -6/z**2 + 15/z**4
    >>> fn(4, z)
    1/z - 45/z**3 + 105/z**5

    """

    if n < 0:
        dup = dup_spherical_bessel_fn_minus(-int(n), ZZ)
    else:
        dup = dup_spherical_bessel_fn(int(n), ZZ)

    poly = DMP(dup, ZZ)

    if x is not None:
        poly = Poly.new(poly, 1/x)
    else:
        poly = PurePoly.new(poly, 1/Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 14
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def chebyshevu_poly(n, x=None, **args):
    """Generates Chebyshev polynomial of the second kind of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate 2nd kind Chebyshev polynomial of degree %s" % n)

    poly = DMP(dup_chebyshevu(int(n), ZZ), ZZ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 15
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def legendre_poly(n, x=None, **args):
    """Generates Legendre polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Legendre polynomial of degree %s" % n)

    poly = DMP(dup_legendre(int(n), QQ), QQ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 16
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def chebyshevt_poly(n, x=None, **args):
    """Generates Chebyshev polynomial of the first kind of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate 1st kind Chebyshev polynomial of degree %s" % n)

    if x is not None:
        x = sympify(x)
    else:
        x = Dummy('x')

    poly = Poly.new(DMP(dup_chebyshevt(int(n), ZZ), ZZ), x)

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 17
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def hermite_poly(n, x=None, **args):
    """Generates Hermite polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Hermite polynomial of degree %s" % n)

    if x is not None:
        x = sympify(x)
    else:
        x = Dummy('x')

    poly = Poly.new(DMP(dup_hermite(int(n), ZZ), ZZ), x)

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 18
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def cyclotomic_poly(n, x=None, **args):
    """Generates cyclotomic polynomial of order `n` in `x`. """
    if n <= 0:
        raise ValueError("can't generate cyclotomic polynomial of order %s" % n)

    if x is not None:
        x = sympify(x)
    else:
        x = Dummy('x')

    poly = Poly.new(DMP(dup_zz_cyclotomic_poly(int(n), ZZ), ZZ), x)

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 19
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def cyclotomic_poly(n, x=None, **args):
    """Generates cyclotomic polynomial of order `n` in `x`. """
    if n <= 0:
        raise ValueError("can't generate cyclotomic polynomial of order %s" % n)

    poly = DMP(dup_zz_cyclotomic_poly(int(n), ZZ), ZZ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy("x"))

    if not args.get("polys", False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 20
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def hermite_poly(n, x=None, **args):
    """Generates Hermite polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Hermite polynomial of degree %s" % n)

    if x is not None:
        x = sympify(x)
    else:
        x = Dummy('x')

    poly = Poly.new(DMP(dup_hermite(int(n), ZZ), ZZ), x)

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 21
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def legendre_poly(n, x=None, **args):
    """Generates Legendre polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Legendre polynomial of degree %s" % n)

    poly = DMP(dup_legendre(int(n), QQ), QQ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 22
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def spherical_bessel_fn(n, x=None, **args):
    """
    Coefficients for the spherical Bessel functions.

    Those are only needed in the jn() function.

    The coefficients are calculated from:

    fn(0, z) = 1/z
    fn(1, z) = 1/z**2
    fn(n-1, z) + fn(n+1, z) == (2*n+1)/z * fn(n, z)

    Examples
    ========

    >>> from sympy.polys.orthopolys import spherical_bessel_fn as fn
    >>> from sympy import Symbol
    >>> z = Symbol("z")
    >>> fn(1, z)
    z**(-2)
    >>> fn(2, z)
    -1/z + 3/z**3
    >>> fn(3, z)
    -6/z**2 + 15/z**4
    >>> fn(4, z)
    1/z - 45/z**3 + 105/z**5

    """
    from sympy import sympify

    if n < 0:
        dup = dup_spherical_bessel_fn_minus(-int(n), ZZ)
    else:
        dup = dup_spherical_bessel_fn(int(n), ZZ)

    poly = DMP(dup, ZZ)

    if x is not None:
        poly = Poly.new(poly, 1 / x)
    else:
        poly = PurePoly.new(poly, 1 / Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 23
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def jacobi_poly(n, a, b, x=None, **args):
    """Generates Jacobi polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Jacobi polynomial of degree %s" % n)

    K, v = construct_domain([a, b], field=True)
    poly = DMP(dup_jacobi(int(n), v[0], v[1], K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 24
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def gegenbauer_poly(n, a, x=None, **args):
    """Generates Gegenbauer polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Gegenbauer polynomial of degree %s" % n)

    K, a = construct_domain(a, field=True)
    poly = DMP(dup_gegenbauer(int(n), a, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 25
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def chebyshevt_poly(n, x=None, **args):
    """Generates Chebyshev polynomial of the first kind of degree `n` in `x`. """
    if n < 0:
        raise ValueError(
            "can't generate 1st kind Chebyshev polynomial of degree %s" % n)

    if x is not None:
        x = sympify(x)
    else:
        x = Dummy('x')

    poly = Poly.new(DMP(dup_chebyshevt(int(n), ZZ), ZZ), x)

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 26
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def cyclotomic_poly(n, x=None, **args):
    """Generates cyclotomic polynomial of order `n` in `x`. """
    if n <= 0:
        raise ValueError("can't generate cyclotomic polynomial of order %s" %
                         n)

    poly = DMP(dup_zz_cyclotomic_poly(int(n), ZZ), ZZ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 27
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def jacobi_poly(n, a, b, x=None, **args):
    """Generates Jacobi polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Jacobi polynomial of degree %s" % n)

    K, v = construct_domain([a, b], field=True)
    poly = DMP(dup_jacobi(int(n), v[0], v[1], K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 28
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def chebyshevu_poly(n, x=None, **args):
    """Generates Chebyshev polynomial of the second kind of degree `n` in `x`. """
    if n < 0:
        raise ValueError(
            "can't generate 2nd kind Chebyshev polynomial of degree %s" % n)

    poly = DMP(dup_chebyshevu(int(n), ZZ), ZZ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 29
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def spherical_bessel_fn(n, x=None, **args):
    """
    Coefficients for the spherical Bessel functions.

    Those are only needed in the jn() function.

    The coefficients are calculated from:

    fn(0, z) = 1/z
    fn(1, z) = 1/z**2
    fn(n-1, z) + fn(n+1, z) == (2*n+1)/z * fn(n, z)

    Examples
    ========

    >>> from sympy.polys.orthopolys import spherical_bessel_fn as fn
    >>> from sympy import Symbol
    >>> z = Symbol("z")
    >>> fn(1, z)
    z**(-2)
    >>> fn(2, z)
    -1/z + 3/z**3
    >>> fn(3, z)
    -6/z**2 + 15/z**4
    >>> fn(4, z)
    1/z - 45/z**3 + 105/z**5

    """
    from sympy import sympify

    if n < 0:
        dup = dup_spherical_bessel_fn_minus(-int(n), ZZ)
    else:
        dup = dup_spherical_bessel_fn(int(n), ZZ)

    poly = DMP(dup, ZZ)

    if x is not None:
        poly = Poly.new(poly, 1/x)
    else:
        poly = PurePoly.new(poly, 1/Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 30
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def gegenbauer_poly(n, a, x=None, **args):
    """Generates Gegenbauer polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Gegenbauer polynomial of degree %s" %
                         n)

    K, a = construct_domain(a, field=True)
    poly = DMP(dup_gegenbauer(int(n), a, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 31
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def laguerre_poly(n, x=None, alpha=None, **args):
    """Generates Laguerre polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Laguerre polynomial of degree %s" % n)

    if alpha is not None:
        K, alpha = construct_domain(alpha, field=True) # XXX: ground_field=True
    else:
        K, alpha = QQ, QQ(0)

    poly = DMP(dup_laguerre(int(n), alpha, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 32
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def laguerre_poly(n, x=None, alpha=None, **args):
    """Generates Laguerre polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Laguerre polynomial of degree %s" % n)

    if alpha is not None:
        K, alpha = construct_domain(alpha,
                                    field=True)  # XXX: ground_field=True
    else:
        K, alpha = QQ, QQ(0)

    poly = DMP(dup_laguerre(int(n), alpha, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
Exemplo n.º 33
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def legendre_poly(n, x=None, polys=False):
    """Generates Legendre polynomial of degree `n` in `x`.

    Parameters
    ----------
    n : int
        `n` decides the degree of polynomial
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError("can't generate Legendre polynomial of degree %s" % n)

    poly = DMP(dup_legendre(int(n), QQ), QQ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
Exemplo n.º 34
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def cyclotomic_poly(n, x=None, polys=False):
    """Generates cyclotomic polynomial of order `n` in `x`.

    Parameters
    ----------
    n : int
        `n` decides the order of polynomial
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n <= 0:
        raise ValueError("can't generate cyclotomic polynomial of order %s" % n)

    poly = DMP(dup_zz_cyclotomic_poly(int(n), ZZ), ZZ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy("x"))

    return poly if polys else poly.as_expr()
Exemplo n.º 35
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def cyclotomic_poly(n, x=None, polys=False):
    """Generates cyclotomic polynomial of order `n` in `x`.

    Parameters
    ----------
    n : int
        `n` decides the order of polynomial
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n <= 0:
        raise ValueError(
            "can't generate cyclotomic polynomial of order %s" % n)

    poly = DMP(dup_zz_cyclotomic_poly(int(n), ZZ), ZZ)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()