choose one name for partial fraction decompositions

[jasongrout]

Two different ways to do partial fractions should have the same function name:

sage: x=polygen(QQ)
sage: f=(x - 3)/((x +1)*(x-1))
sage: f.partial_fraction_decomposition()
(0, [-1/(x - 1), 2/(x + 1)])
sage: x=var('x')
sage: f=(x - 3)/((x +1)*(x-1))
sage: f.partial_fraction()
2/(x + 1) - 1/(x - 1)

An added bonus would be if they gave similar output (currently one gives a list, the other gives an expression).

Component: algebra

Author: Frédéric Chapoton

Branch/Commit: 48de749

Reviewer: Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/4039

[robertwb]

comment:1

Note that there's no way to "symbolically" unevaluated sums of fraction field elements in Frac(QQ[x])

[fchapoton]

New commits:

48de749

add the method partial_fraction_decomposition to symbolic expressions

[fchapoton]

Commit: 48de749

[fchapoton]

Branch: u/chapoton/4039

[fchapoton]

Author: Frédéric Chapoton

[mkoeppe]

comment:7

Returning the result as a FormalSum could also be nice

[mkoeppe]

Reviewer: Matthias Koeppe

[vbraun]

Changed branch from u/chapoton/4039 to 48de749