#8259: Conversion from symmetric polynomials to basis of monomial symmetric
functions
-----------------------------+----------------------------------------------
Reporter: aschilling | Owner: sage-combinat
Type: enhancement | Status: new
Priority: major | Milestone:
Component: combinatorics | Keywords: symmetric functions
Author: | Upstream: N/A
Reviewer: | Merged:
Work_issues: |
-----------------------------+----------------------------------------------
Currently a function that converts a symmetric polynomial into the
monomial basis is missing in sage. Jason Bandlow wrote a first version
which should be integrated into sage:
def toSF(f):
""" Input is a symmetric polynomial in a polynomial ring in finitely
many variables. Output is a symmetric function in the monomial
basis of the ring of symmetric functions over the same base ring.
"""
X = f.parent().gens()
n = f.parent().ngens()
SF = SymmetricFunctions(f.base_ring())
m = SF.monomial()
out = m(0)
while f != 0:
lt = f.lt()
c = lt.monomial_coefficient(lt)
p = Partition(lt.exponents()[0])
f += -c*m(p).expand(n,X)
out += c*m(p)
return out
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/8259>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en.
