Esempio n. 1
0
    def _s_to_self_base(self, part):
        r"""
        Returns a function which gives the coefficient of a partition
        in the expansion of the Schur functions ``s(part)`` in the Hall-Littlewood
        `P` basis.

        INPUT:

        - ``self`` -- an instance of the Hall-Littlewood `P` basis
        - ``part`` -- a partition

        OUTPUT:

        - returns a function which accepts a partition ``part2`` and returns
          the coefficient of ``P(part2)`` in ``s(part)``
          This coefficient is the t-Kostka-Foulkes polynomial  `K_{part,part2}(t)`

        EXAMPLES::

            sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
            sage: HLP = Sym.hall_littlewood().P()
            sage: f21 = HLP._s_to_self_base(Partition([2,1]))
            sage: [f21(p) for p in Partitions(3)]
            [0, 1, t^2 + t]
        """
        t = QQt.gen()
        zero = self.base_ring()(0)
        res_dict = kfpoly.schur_to_hl(part, t)
        f = lambda part2: res_dict.get(part2, zero)
        return f
Esempio n. 2
0
    def _s_to_self_base(self, part):
        r"""
        Returns a function which gives the coefficient of a partition
        in the expansion of the Schur functions ``s(part)`` in the Hall-Littlewood
        `P` basis.

        INPUT:

        - ``self`` -- an instance of the Hall-Littlewood `P` basis
        - ``part`` -- a partition

        OUTPUT:

        - returns a function which accepts a partition ``part2`` and returns
          the coefficient of ``P(part2)`` in ``s(part)``
          This coefficient is the t-Kostka-Foulkes polynomial  `K_{part,part2}(t)`

        EXAMPLES::

            sage: Sym = SymmetricFunctions(FractionField(QQ['t']))
            sage: HLP = Sym.hall_littlewood().P()
            sage: f21 = HLP._s_to_self_base(Partition([2,1]))
            sage: [f21(p) for p in Partitions(3)]
            [0, 1, t^2 + t]
        """
        t = QQt.gen()
        zero = self.base_ring()(0)
        res_dict = kfpoly.schur_to_hl(part, t)
        f = lambda part2: res_dict.get(part2,zero)
        return f
Esempio n. 3
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 def _s_to_self_base(self, part):
     """
     Returns a function which gives the coefficient of a partition
     in the expansion of the Schur functions ``s(part)`` in self.
     
     EXAMPLES::
     
         sage: P = HallLittlewoodP(QQ)
         sage: f21 = P._s_to_self_base(Partition([2,1]))
         sage: [f21(p) for p in Partitions(3)]
         [0, 1, t^2 + t]
     """
     Zt = ZZ['t']
     t = Zt.gen()
     zero = Zt(0)
     res_dict = kfpoly.schur_to_hl(part, t)
     f = lambda part2: res_dict.get(part2, zero)
     return f
Esempio n. 4
0
 def _s_to_self_base(self, part):
     """
     Returns a function which gives the coefficient of a partition
     in the expansion of the Schur functions ``s(part)`` in self.
     
     EXAMPLES::
     
         sage: P = HallLittlewoodP(QQ)
         sage: f21 = P._s_to_self_base(Partition([2,1]))
         sage: [f21(p) for p in Partitions(3)]
         [0, 1, t^2 + t]
     """
     Zt = ZZ['t']
     t = Zt.gen()
     zero = Zt(0)
     res_dict = kfpoly.schur_to_hl(part, t)
     f = lambda part2: res_dict.get(part2,zero)
     return f