def expand(self):
"""
EXAMPLES::
sage: X = SchubertPolynomialRing(ZZ)
sage: X([2,1,3]).expand()
x0
sage: map(lambda x: x.expand(), [X(p) for p in Permutations(3)])
[1, x0 + x1, x0, x0*x1, x0^2, x0^2*x1]
TESTS: Calling .expand() should always return an element of an
MPolynomialRing
::
sage: X = SchubertPolynomialRing(ZZ)
sage: f = X([1]); f
X[1]
sage: type(f.expand())
<type 'sage.rings.polynomial.multi_polynomial_libsingular.MPolynomial_libsingular'>
sage: f.expand()
1
sage: f = X([1,2])
sage: type(f.expand())
<type 'sage.rings.polynomial.multi_polynomial_libsingular.MPolynomial_libsingular'>
sage: f = X([1,3,2,4])
sage: type(f.expand())
<type 'sage.rings.polynomial.multi_polynomial_libsingular.MPolynomial_libsingular'>
"""
p = symmetrica.t_SCHUBERT_POLYNOM(self)
if not is_MPolynomial(p):
R = PolynomialRing(self.parent().base_ring(), 1, 'x')
p = R(p)
return p
def expand(self):
"""
EXAMPLES::
sage: X = SchubertPolynomialRing(ZZ)
sage: X([2,1,3]).expand()
x0
sage: map(lambda x: x.expand(), [X(p) for p in Permutations(3)])
[1, x0 + x1, x0, x0*x1, x0^2, x0^2*x1]
TESTS: Calling .expand() should always return an element of an
MPolynomialRing
::
sage: X = SchubertPolynomialRing(ZZ)
sage: f = X([1]); f
X[1]
sage: type(f.expand())
<type 'sage.rings.polynomial.multi_polynomial_libsingular.MPolynomial_libsingular'>
sage: f.expand()
1
sage: f = X([1,2])
sage: type(f.expand())
<type 'sage.rings.polynomial.multi_polynomial_libsingular.MPolynomial_libsingular'>
sage: f = X([1,3,2,4])
sage: type(f.expand())
<type 'sage.rings.polynomial.multi_polynomial_libsingular.MPolynomial_libsingular'>
"""
p = symmetrica.t_SCHUBERT_POLYNOM(self)
if not is_MPolynomial(p):
R = PolynomialRing(self.parent().base_ring(), 1, 'x')
p = R(p)
return p