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# Jack Symmetric Functions

Jack’s symmetric functions appear in [Ma1995] Chapter VI, section 10. Zonal polynomials are the subject of [Ma1995] Chapter VII. The parameter \(\alpha\) in that reference is the parameter \(t\) in this implementation in sage.

REFERENCES:

[Jack1970] | H. Jack, A class of symmetric functions with a parameter, Proc. R. Soc. Edinburgh (A), 69, 1-18.

[Ma1995] | (1, 2) I. G. Macdonald, Symmetric functions and Hall polynomials, second ed., The Clarendon Press, Oxford University Press, New York, 1995, With contributions by A. Zelevinsky, Oxford Science Publications.

class `sage.combinat.sf.jack.``Jack`(Sym, t='t')

  Bases: `sage.structure.unique_representation.UniqueRepresentation`

  The family of Jack symmetric functions including the \(P\), \(Q\), \(J\), \(Qp\) bases. The default parameter is `t`.

  INPUT:

  - `self` – the family of Jack symmetric function bases
  - `Sym` – a ring of symmetric functions
  - `t` – an optional parameter (default : ‘t’)

  EXAMPLES:

      sage: SymmetricFunctions(FractionField(QQ['t'])).jack()
      Jack polynomials over Fraction Field of Univariate Polynomial Ring in t over Rational Field
      sage: SymmetricFunctions(QQ).jack(1)
      Jack polynomials with t=1 over Rational Field

  `J`()

    Returns the algebra of Jack polynomials in the \(J\) basis.

    INPUT:

    - `self` – the family of Jack symmetric function bases

    OUTPUT: the \(J\) basis of the Jack symmetric functions

    EXAMPLES:

        sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
        sage: JJ = Sym.jack().J(); JJ
        Symmetric Functions over Fraction Field of Univariate Polynomial Ring in t over Rational Field in the Jack J basis
        sage: Sym = SymmetricFunctions(QQ)
        sage: Sym.jack(t=-1).J()
        Symmetric Functions over Rational Field in the Jack J with t=-1 basis

    At \(t = 1\), the Jack polynomials in the \(J\) basis are scalar multiples of the Schur functions with the scalar given by a Partition’s `hook_product()` method at 1:

        sage: Sym = SymmetricFunctions(QQ)
        sage: JJ = Sym.jack(t=1).J()
        sage: s = Sym.schur()
        sage: p = Partition([3,2,1,1])
        sage: s(JJ(p)) == p.hook_product(1)*s(p)  # long time (4s on sage.math, 2012)
        True

    At \(t = 2\), the Jack polynomials in the \(J\) basis are scalar multiples of the zonal polynomials with the scalar given by a Partition’s `hook_product()` method at 2.

        sage: Sym = SymmetricFunctions(QQ)
        sage: JJ = Sym.jack(t=2).J()
        sage: Z = Sym.zonal()
        sage: p = Partition([2,2,1])
        sage: Z(JJ(p)) == p.hook_product(2)*Z(p)
        True

        sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
        sage: JJ = Sym.jack().J()
        sage: JP = Sym.jack().P()
        sage: JJ(sum(JP(p) for p in Partitions(3)))
        1/6*JackJ[1, 1, 1] + (1/(t+2))*JackJ[2, 1] + (1/(2*t^2+3*t+1))*JackJ[3]

        sage: s = Sym.schur()
        sage: JJ(s([3])) # indirect doctest
        ((t^2-3*t+2)/(6*t^2+18*t+12))*JackJ[1, 1, 1] + ((2*t-2)/(2*t^2+5*t+2))*JackJ[2, 1] + (1/(2*t^2+3*t+1))*JackJ[3]
        sage: JJ(s([2,1]))
        ((t-1)/(3*t+6))*JackJ[1, 1, 1] + (1/(t+2))*JackJ[2, 1]
        sage: JJ(s([1,1,1]))
        1/6*JackJ[1, 1, 1]

  `P`()

    Returns the algebra of Jack polynomials in the \(P\) basis.

    INPUT:

    - `self` – the family of Jack symmetric function bases

    OUTPUT:

    - the \(P\) basis of the Jack symmetric functions

    EXAMPLES:

        sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
        sage: JP = Sym.jack().P(); JP
        Symmetric Functions over Fraction Field of Univariate Polynomial Ring in t over Rational Field in the Jack P basis
        sage: Sym.jack(t=-1).P()
        Symmetric Functions over Fraction Field of Univariate Polynomial Ring in t over Rational Field in the Jack P with t=-1 basis

    At \(t = 1\), the Jack polynomials in the \(P\) basis are the Schur symmetric functions.

        sage: Sym = SymmetricFunctions(QQ)
        sage: JP = Sym.jack(t=1).P()
        sage: s = Sym.schur()
        sage: s(JP([2,2,1]))
        s[2, 2, 1]
        sage: JP(s([2,2,1]))
        JackP[2, 2, 1]
        sage: JP([2,1])^2
        JackP[2, 2, 1, 1] + JackP[2, 2, 2] + JackP[3, 1, 1, 1] + 2*JackP[3, 2, 1] + JackP[3, 3] + JackP[4, 1, 1] + JackP[4, 2]

    At \(t = 2\), the Jack polynomials in the \(P\) basis are the zonal polynomials.

        sage: Sym = SymmetricFunctions(QQ)
        sage: JP = Sym.jack(t=2).P()
        sage: Z = Sym.zonal()
        sage: Z(JP([2,2,1]))
        Z[2, 2, 1]
        sage: JP(Z[2, 2, 1])
        JackP[2, 2, 1]
        sage: JP([2])^2
        64/45*JackP[2, 2] + 16/21*JackP[3, 1] + JackP[4]
        sage: Z([2])^2
        64/45*Z[2, 2] + 16/21*Z[3, 1] + Z[4]

    ::

        sage: Sym = SymmetricFunctions(QQ['a','b'].fraction_field())
        sage: (a,b) = Sym.base_ring().gens()
        sage: Jacka = Sym.jack(t=a)
        sage: Jackb = Sym.jack(t=b)
        sage: m = Sym.monomial()
        sage: JPa = Jacka.P()
        sage: JPb = Jackb.P()
        sage: m(JPa[2,1])
        (6/(a+2))*m[1, 1, 1] + m[2, 1]
        sage: m(JPb[2,1])
        (6/(b+2))*m[1, 1, 1] + m[2, 1]
        sage: m(a*JPb([2,1]) + b*JPa([2,1]))
        ((6*a^2+6*b^2+12*a+12*b)/(a*b+2*a+2*b+4))*m[1, 1, 1] + (a+b)*m[2, 1]
        sage: JPa(JPb([2,1]))
        ((6*a-6*b)/(a*b+2*a+2*b+4))*JackP[1, 1, 1] + JackP[2, 1]

        sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
        sage: JQ = Sym.jack().Q()
        sage: JP = Sym.jack().P()
        sage: JJ = Sym.jack().J()

        sage: JP(JQ([2,1]))
        ((t+2)/(2*t^3+t^2))*JackP[2, 1]
        sage: JP(JQ([3]))
        ((2*t^2+3*t+1)/(6*t^3))*JackP[3]
        sage: JP(JQ([1,1,1]))
        (6/(t^3+3*t^2+2*t))*JackP[1, 1, 1]

        sage: JP(JJ([3]))
        (2*t^2+3*t+1)*JackP[3]
        sage: JP(JJ([2,1]))
        (t+2)*JackP[2, 1]
        sage: JP(JJ([1,1,1]))
        6*JackP[1, 1, 1]

        sage: s = Sym.schur()
        sage: JP(s([2,1]))
        ((2*t-2)/(t+2))*JackP[1, 1, 1] + JackP[2, 1]
        sage: s(_)
        s[2, 1]

  `Q`()

    Returns the algebra of Jack polynomials in the \(Q\) basis.

    INPUT:

    - `self` – the family of Jack symmetric function bases

    OUTPUT:

    - the \(Q\) basis of the Jack symmetric functions

    EXAMPLES:

        sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
        sage: JQ = Sym.jack().Q(); JQ
        Symmetric Functions over Fraction Field of Univariate Polynomial Ring in t over Rational Field in the Jack Q basis
        sage: Sym = SymmetricFunctions(QQ)
        sage: Sym.jack(t=-1).Q()
        Symmetric Functions over Rational Field in the Jack Q with t=-1 basis

        sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
        sage: JQ = Sym.jack().Q()
        sage: JP = Sym.jack().P()
        sage: JQ(sum(JP(p) for p in Partitions(3)))
        (1/6*t^3+1/2*t^2+1/3*t)*JackQ[1, 1, 1] + ((2*t^3+t^2)/(t+2))*JackQ[2, 1] + (6*t^3/(2*t^2+3*t+1))*JackQ[3]

        sage: s = Sym.schur()
        sage: JQ(s([3])) # indirect doctest
        (1/6*t^3-1/2*t^2+1/3*t)*JackQ[1, 1, 1] + ((2*t^3-2*t^2)/(t+2))*JackQ[2, 1] + (6*t^3/(2*t^2+3*t+1))*JackQ[3]
        sage: JQ(s([2,1]))
        (1/3*t^3-1/3*t)*JackQ[1, 1, 1] + ((2*t^3+t^2)/(t+2))*JackQ[2, 1]
        sage: JQ(s([1,1,1]))
        (1/6*t^3+1/2*t^2+1/3*t)*JackQ[1, 1, 1]

  `Qp`()

    Returns the algebra of Jack polynomials in the \(Qp\), which is dual to the \(P\) basis with respect to the standard scalar product.

    INPUT:

    - `self` – the family of Jack symmetric function bases

    OUTPUT:

    - the \(Q'\) basis of the Jack symmetric functions

    EXAMPLES:

        sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
        sage: JP = Sym.jack().P()
        sage: JQp = Sym.jack().Qp(); JQp
        Symmetric Functions over Fraction Field of Univariate Polynomial Ring in t over Rational Field in the Jack Qp basis
        sage: a = JQp([2])
        sage: a.scalar(JP([2]))
        1
        sage: a.scalar(JP([1,1]))
        0
        sage: JP(JQp([2]))                        # todo: missing auto normalization
        ((t-1)/(t+1))*JackP[1, 1] + JackP[2]
        sage: JP._normalize(JP(JQp([2])))
        ((t-1)/(t+1))*JackP[1, 1] + JackP[2]

  `base_ring`()

    Returns the base ring of the symmetric functions in which the Jack symmetric functions live

    INPUT:

    - `self` – the family of Jack symmetric function bases

    OUTPUT:

    - the base ring of the symmetric functions ring of `self`

    EXAMPLES:

        sage: J2 = SymmetricFunctions(QQ).jack(t=2)
        sage: J2.base_ring()
        Rational Field

  `symmetric_function_ring`()

    Returns the base ring of the symmetric functions of the Jack symmetric function bases

    INPUT:

    - `self` – the family of Jack symmetric function bases

    OUTPUT:

    - the symmetric functions ring of `self`

    EXAMPLES:

        sage: Jacks = SymmetricFunctions(FractionField(QQ['t'])).jack()
        sage: Jacks.symmetric_function_ring()
        Symmetric Functions over Fraction Field of Univariate Polynomial Ring in t over Rational Field

class `sage.combinat.sf.jack.``JackPolynomials_generic`(jack)

  Bases: `sage.combinat.sf.sfa.SymmetricFunctionAlgebra_generic`

  A class of methods which are common to all Jack bases of the symmetric functions

  INPUT:

  - `self` – a Jack basis of the symmetric functions
  - `jack` – a family of Jack symmetric function bases

  EXAMPLES

      sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
      sage: JP = Sym.jack().P(); JP.base_ring()
      Fraction Field of Univariate Polynomial Ring in t over Rational Field
      sage: Sym = SymmetricFunctions(QQ)
      sage: JP = Sym.jack(t=2).P(); JP.base_ring()
      Rational Field

  class `Element`(M, x)

    Bases: `sage.combinat.sf.sfa.SymmetricFunctionAlgebra_generic_Element`

    Create a combinatorial module element. This should never be called directly, but only through the parent combinatorial free module’s `__call__()` method.

    TESTS:

        sage: F = CombinatorialFreeModule(QQ, ['a','b','c'])
        sage: B = F.basis()
        sage: f = B['a'] + 3*B['c']; f
        B['a'] + 3*B['c']
        sage: f == loads(dumps(f))
        True

    `scalar_jack`(x, t=None)

      A scalar product where the power sums are orthogonal and \(\langle p_\mu, p_\mu \rangle = z_\mu t^{length(\mu)}\)

      INPUT:

      - `self` – an element of a Jack basis of the symmetric functions

      - `x` – an element of the symmetric functions

      - `t` – an optional parameter (default : None uses the parameter from

          the basis)

      OUTPUT:

      - returns the Jack scalar product between `x` and `self`

      EXAMPLES:

          sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
          sage: JP = Sym.jack().P()
          sage: JQ = Sym.jack().Q()
          sage: p = Partitions(3).list()
          sage: matrix([[JP(a).scalar_jack(JQ(b)) for a in p] for b in p])
          [1 0 0]
          [0 1 0]
          [0 0 1]

  `JackPolynomials_generic.``c1`(part)

    Returns the \(t\)-Jack scalar product between `J(part)` and `P(part)`.

    INPUT:

    - `self` – a Jack basis of the symmetric functions
    - `part` – a partition
    - `t` – an optional parameter (default: uses the parameter \(t\) from the Jack basis)

    OUTPUT:

    - a polynomial in the parameter `t` which is equal to the scalar product of `J(part)` and `P(part)`

    EXAMPLES

        sage: JP = SymmetricFunctions(FractionField(QQ['t'])).jack().P()
        sage: JP.c1(Partition([2,1]))
        t + 2

  `JackPolynomials_generic.``c2`(part)

    Returns the \(t\)-Jack scalar product between `J(part)` and `Q(part)`.

    INPUT:

    - `self` – a Jack basis of the symmetric functions

    - `part` – a partition

    - `t` – an optional parameter (default: uses the parameter \(t\) from the

        Jack basis)

    OUTPUT:

    - a polynomial in the parameter `t` which is equal to the scalar product of `J(part)` and `Q(part)`

    EXAMPLES:

        sage: JP = SymmetricFunctions(FractionField(QQ['t'])).jack().P()
        sage: JP.c2(Partition([2,1]))
        2*t^3 + t^2

  `JackPolynomials_generic.``coproduct_by_coercion`(elt)

    Returns the coproduct of the element `elt` by coercion to the Schur basis.

    INPUT:

    - `self` – a Jack symmetric function basis
    - `elt` – an instance of this basis

    OUTPUT:

    - The coproduct acting on `elt`, the result is an element of the tensor squared of the Jack symmetric function basis

    EXAMPLES:

        sage: Sym = SymmetricFunctions(QQ['t'].fraction_field())
        sage: Sym.jack().P()[2,2].coproduct() #indirect doctest
        JackP[] # JackP[2, 2] + (2/(t+1))*JackP[1] # JackP[2, 1] + ((8*t+4)/(t^3+4*t^2+5*t+2))*JackP[1, 1] # JackP[1, 1] + JackP[2] # JackP[2] + (2/(t+1))*JackP[2, 1] # JackP[1] + JackP[2, 2] # JackP[]

  `JackPolynomials_generic.``jack_family`()

    Returns the family of Jack bases associated to the basis `self`

    INPUT:

    - `self` – a Jack basis of the symmetric functions

    OUTPUT:

    - the family of Jack symmetric functions associated to `self`

    EXAMPLES:

        sage: JackP = SymmetricFunctions(QQ).jack(t=2).P()
        sage: JackP.jack_family()
        Jack polynomials with t=2 over Rational Field

class `sage.combinat.sf.jack.``JackPolynomials_j`(jack)

  Bases: `sage.combinat.sf.jack.JackPolynomials_generic`

  The \(J\) basis is a defined as a normalized form of the \(P\) basis

  INPUT:

  - `self` – an instance of the Jack \(P\) basis of the symmetric functions
  - `jack` – a family of Jack symmetric function bases

  EXAMPLES:

      sage: J = SymmetricFunctions(FractionField(QQ['t'])).jack().J()
      sage: TestSuite(J).run(skip=['_test_associativity', '_test_distributivity', '_test_prod']) # products are too expensive
      sage: TestSuite(J).run(elements = [J.t*J[1,1]+J[2], J[1]+(1+J.t)*J[1,1]])  # long time (3s on sage.math, 2012)

  class `Element`(M, x)

    Bases: `sage.combinat.sf.jack.JackPolynomials_generic.Element`

    Create a combinatorial module element. This should never be called directly, but only through the parent combinatorial free module’s `__call__()` method.

    TESTS:

        sage: F = CombinatorialFreeModule(QQ, ['a','b','c'])
        sage: B = F.basis()
        sage: f = B['a'] + 3*B['c']; f
        B['a'] + 3*B['c']
        sage: f == loads(dumps(f))
        True

class `sage.combinat.sf.jack.``JackPolynomials_p`(jack)

  Bases: `sage.combinat.sf.jack.JackPolynomials_generic`

  The \(P\) basis is uni-triangularly related to the monomial basis and orthogonal with respect to the Jack scalar product.

  INPUT:

  - `self` – an instance of the Jack \(P\) basis of the symmetric functions
  - `jack` – a family of Jack symmetric function bases

  EXAMPLES:

      sage: P = SymmetricFunctions(FractionField(QQ['t'])).jack().P()
      sage: TestSuite(P).run(skip=['_test_associativity', '_test_distributivity', '_test_prod']) # products are too expensive
      sage: TestSuite(P).run(elements = [P.t*P[1,1]+P[2], P[1]+(1+P.t)*P[1,1]])

  class `Element`(M, x)

    Bases: `sage.combinat.sf.jack.JackPolynomials_generic.Element`

    Create a combinatorial module element. This should never be called directly, but only through the parent combinatorial free module’s `__call__()` method.

    TESTS:

        sage: F = CombinatorialFreeModule(QQ, ['a','b','c'])
        sage: B = F.basis()
        sage: f = B['a'] + 3*B['c']; f
        B['a'] + 3*B['c']
        sage: f == loads(dumps(f))
        True

    `scalar_jack`(x, t=None)

      The scalar product on the symmetric functions where the power sums are orthogonal and \(\langle p_\mu, p_\mu \rangle = z_\mu t^{length(mu)}\) where the t parameter from the Jack symmetric function family.

      INPUT:

      - `self` – an element of the Jack \(P\) basis
      - `x` – an element of the \(P\) basis

      EXAMPLES

          sage: JP = SymmetricFunctions(FractionField(QQ['t'])).jack().P()
          sage: l = [JP(p) for p in Partitions(3)]
          sage: matrix([[a.scalar_jack(b) for a in l] for b in l])
          [  6*t^3/(2*t^2 + 3*t + 1)                         0                         0]
          [                        0     (2*t^3 + t^2)/(t + 2)                         0]
          [                        0                         0 1/6*t^3 + 1/2*t^2 + 1/3*t]

  `JackPolynomials_p.``scalar_jack_basis`(part1, part2=None)

    Returns the scalar product of \(P(part1)\) and \(P(part2)\).

    This is equation (10.16) of [Mc1995] on page 380.

    INPUT:

    - `self` – an instance of the Jack \(P\) basis of the symmetric functions
    - `part1` – a partition
    - `part2` – an optional partition (default : None)

    OUTPUT:

    - the scalar product between \(P(part1)\) and \(P(part2)\) (or itself if \(part2\) is None)

    REFRENCES:

    > [Mc1995] | I. G. Macdonald, Symmetric functions and Hall polynomials, second ed., The Clarendon Press, Oxford University Press, New York, 1995, With contributions by A. Zelevinsky, Oxford Science Publications.

    EXAMPLES:

        sage: JP = SymmetricFunctions(FractionField(QQ['t'])).jack().P()
        sage: JJ = SymmetricFunctions(FractionField(QQ['t'])).jack().J()
        sage: JP.scalar_jack_basis(Partition([2,1]), Partition([1,1,1]))
        0
        sage: JP._normalize_coefficients(JP.scalar_jack_basis(Partition([3,2,1]), Partition([3,2,1])))
        (12*t^6 + 20*t^5 + 11*t^4 + 2*t^3)/(2*t^3 + 11*t^2 + 20*t + 12)
        sage: JJ(JP[3,2,1]).scalar_jack(JP[3,2,1])
        (12*t^6 + 20*t^5 + 11*t^4 + 2*t^3)/(2*t^3 + 11*t^2 + 20*t + 12)

    With a single argument, takes \(part2 = part1\):

        sage: JP.scalar_jack_basis(Partition([2,1]), Partition([2,1]))
        (2*t^3 + t^2)/(t + 2)
        sage: JJ(JP[2,1]).scalar_jack(JP[2,1])
        (2*t^3 + t^2)/(t + 2)

class `sage.combinat.sf.jack.``JackPolynomials_q`(jack)

  Bases: `sage.combinat.sf.jack.JackPolynomials_generic`

  The \(Q\) basis is defined as a normalized form of the \(P\) basis

  INPUT:

  - `self` – an instance of the Jack \(Q\) basis of the symmetric functions
  - `jack` – a family of Jack symmetric function bases

  EXAMPLES:

      sage: Q = SymmetricFunctions(FractionField(QQ['t'])).jack().Q()
      sage: TestSuite(Q).run(skip=['_test_associativity', '_test_distributivity', '_test_prod']) # products are too expensive
      sage: TestSuite(Q).run(elements = [Q.t*Q[1,1]+Q[2], Q[1]+(1+Q.t)*Q[1,1]])  # long time (3s on sage.math, 2012)

  class `Element`(M, x)

    Bases: `sage.combinat.sf.jack.JackPolynomials_generic.Element`

    Create a combinatorial module element. This should never be called directly, but only through the parent combinatorial free module’s `__call__()` method.

    TESTS:

        sage: F = CombinatorialFreeModule(QQ, ['a','b','c'])
        sage: B = F.basis()
        sage: f = B['a'] + 3*B['c']; f
        B['a'] + 3*B['c']
        sage: f == loads(dumps(f))
        True

class `sage.combinat.sf.jack.``JackPolynomials_qp`(jack)

  Bases: `sage.combinat.sf.jack.JackPolynomials_generic`

  The \(Qp\) basis is the dual basis to the \(P\) basis with respect to the standard scalar product

  INPUT:

  - `self` – an instance of the Jack \(Qp\) basis of the symmetric functions
  - `jack` – a family of Jack symmetric function bases

  EXAMPLES:

      sage: Qp = SymmetricFunctions(FractionField(QQ['t'])).jack().Qp()
      sage: TestSuite(Qp).run(skip=['_test_associativity', '_test_distributivity', '_test_prod']) # products are too expensive
      sage: TestSuite(Qp).run(elements = [Qp.t*Qp[1,1]+Qp[2], Qp[1]+(1+Qp.t)*Qp[1,1]])  # long time (3s on sage.math, 2012)

  class `Element`(M, x)

    Bases: `sage.combinat.sf.jack.JackPolynomials_generic.Element`

    Create a combinatorial module element. This should never be called directly, but only through the parent combinatorial free module’s `__call__()` method.

    TESTS:

        sage: F = CombinatorialFreeModule(QQ, ['a','b','c'])
        sage: B = F.basis()
        sage: f = B['a'] + 3*B['c']; f
        B['a'] + 3*B['c']
        sage: f == loads(dumps(f))
        True

  `JackPolynomials_qp.``coproduct_by_coercion`(elt)

    Returns the coproduct of the element `elt` by coercion to the Schur basis.

    INPUT:

    - `elt` – an instance of the `Qp` basis

    OUTPUT:

    - The coproduct acting on `elt`, the result is an element of the tensor squared of the `Qp` symmetric function basis

    EXAMPLES:

        sage: Sym = SymmetricFunctions(QQ['t'].fraction_field())
        sage: JQp = Sym.jack().Qp()
        sage: JQp[2,2].coproduct()   #indirect doctest
        JackQp[] # JackQp[2, 2] + (2*t/(t+1))*JackQp[1] # JackQp[2, 1] + JackQp[1, 1] # JackQp[1, 1] + ((4*t^3+8*t^2)/(2*t^3+5*t^2+4*t+1))*JackQp[2] # JackQp[2] + (2*t/(t+1))*JackQp[2, 1] # JackQp[1] + JackQp[2, 2] # JackQp[]

class `sage.combinat.sf.jack.``SymmetricFunctionAlgebra_zonal`(Sym)

  Bases: `sage.combinat.sf.sfa.SymmetricFunctionAlgebra_generic`

  Returns the algebra of zonal polynomials.

  INPUT:

  - `self` – a zonal basis of the symmetric functions
  - `Sym` – a ring of the symmetric functions

  EXAMPLES

      sage: Z = SymmetricFunctions(QQ).zonal()
      sage: Z([2])^2
      64/45*Z[2, 2] + 16/21*Z[3, 1] + Z[4]
      sage: Z = SymmetricFunctions(QQ).zonal()
      sage: TestSuite(Z).run(skip=['_test_associativity', '_test_distributivity', '_test_prod']) # products are too expensive
      sage: TestSuite(Z).run(elements = [Z[1,1]+Z[2], Z[1]+2*Z[1,1]])

  class `Element`(M, x)

    Bases: `sage.combinat.sf.sfa.SymmetricFunctionAlgebra_generic_Element`

    Create a combinatorial module element. This should never be called directly, but only through the parent combinatorial free module’s `__call__()` method.

    TESTS:

        sage: F = CombinatorialFreeModule(QQ, ['a','b','c'])
        sage: B = F.basis()
        sage: f = B['a'] + 3*B['c']; f
        B['a'] + 3*B['c']
        sage: f == loads(dumps(f))
        True

    `scalar_zonal`(x)

      The zonal scalar product has the power sum basis and the zonal symmetric functions are orthogonal. In particular, \(\langle p_\mu, p_\mu \rangle = z_\mu 2^{length(\mu)}\).

      INPUT:

      - `self` – an element of the zonal basis
      - `x` – an element of the symmetric function

      OUTPUT:

      - the scalar product between `self` and `x`

      EXAMPLES

          sage: Sym = SymmetricFunctions(QQ)
          sage: Z = Sym.zonal()
          sage: parts = Partitions(3).list()
          sage: matrix([[Z(a).scalar_zonal(Z(b)) for a in parts] for b in parts])
          [16/5    0    0]
          [   0    5    0]
          [   0    0    4]
          sage: p = Z.symmetric_function_ring().power()
          sage: matrix([[Z(p(a)).scalar_zonal(p(b)) for a in parts] for b in parts])
          [ 6  0  0]
          [ 0  8  0]
          [ 0  0 48]

`sage.combinat.sf.jack.``c1`(part, t)

  Returns the \(t\)-Jack scalar product between `J(part)` and `P(part)`.

  INPUT:

  - `part` – a partition
  - `t` – an optional parameter (default: uses the parameter \(t\) from the Jack basis)

  OUTPUT:

  - a polynomial in the parameter `t` which is equal to the scalar product of `J(part)` and `P(part)`

  EXAMPLES:

      sage: from sage.combinat.sf.jack import c1
      sage: t = QQ['t'].gen()
      sage: [c1(p,t) for p in Partitions(3)]
      [2*t^2 + 3*t + 1, t + 2, 6]

`sage.combinat.sf.jack.``c2`(part, t)

  Returns the t-Jack scalar product between `J(part)` and `Q(part)`.

  INPUT:

  - `self` – a Jack basis of the symmetric functions
  - `part` – a partition
  - `t` – an optional parameter (default: uses the parameter \(t\) from the Jack basis)

  OUTPUT:

  - a polynomial in the parameter `t` which is equal to the scalar product of `J(part)` and `Q(part)`

  EXAMPLES:

      sage: from sage.combinat.sf.jack import c2
      sage: t = QQ['t'].gen()
      sage: [c2(p,t) for p in Partitions(3)]
      [6*t^3, 2*t^3 + t^2, t^3 + 3*t^2 + 2*t]

`sage.combinat.sf.jack.``normalize_coefficients`(self, c)

  If our coefficient ring is the field of fractions over a univariate polynomial ring over the rationals, then we should clear both the numerator and denominator of the denominators of their coefficients.

  INPUT:

  - `self` – a Jack basis of the symmetric functions
  - `c` – a coefficient in the base ring of `self`

  OUTPUT:

  - divide numerator and denominator by the greatest common divisor

  EXAMPLES:

      sage: JP = SymmetricFunctions(FractionField(QQ['t'])).jack().P()
      sage: t = JP.base_ring().gen()
      sage: a = 2/(1/2*t+1/2)
      sage: JP._normalize_coefficients(a)
      4/(t + 1)
      sage: a = 1/(1/3+1/6*t)
      sage: JP._normalize_coefficients(a)
      6/(t + 2)
      sage: a = 24/(4*t^2 + 12*t + 8)
      sage: JP._normalize_coefficients(a)
      6/(t^2 + 3*t + 2)

`sage.combinat.sf.jack.``part_scalar_jack`(part1, part2, t)

  Returns the Jack scalar product between `p(part1)` and `p(part2)` where \(p\) is the power-sum basis.

  INPUT:

  - `part1`, `part2` – two partitions
  - `t` – a parameter

  OUTPUT:

  - returns the scalar product between the power sum indexed by `part1` and `part2`

  EXAMPLES:

      sage: Q.<t> = QQ[]
      sage: from sage.combinat.sf.jack import part_scalar_jack
      sage: matrix([[part_scalar_jack(p1,p2,t) for p1 in Partitions(4)] for p2 in Partitions(4)])
      [   4*t      0      0      0      0]
      [     0  3*t^2      0      0      0]
      [     0      0  8*t^2      0      0]
      [     0      0      0  4*t^3      0]
      [     0      0      0      0 24*t^4]

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