normalization in Pynac buggy

[rwst]

from https://groups.google.com/forum/?hl=en#!topic/sage-devel/awa0lNGJugo
Minimal version:

sage: a,b,c,d,e=var('a,b,c,d,e')
sage: (c/a - b*c^2/(a^2*(b*c/a-d)) + c*d/(a*(b*c/a-d))).normalize()
0
sage: (e + c/a - b*c^2/(a^2*(b*c/a-d)) + c*d/(a*(b*c/a-d))).normalize()
(a^2*b*c*e - a^3*d*e)/((b*c - a*d)*a^2)

This changed somewhere between 6.6 (output e) and 7.0.

See pynac/pynac#111

Depends on #21034

Upstream: Fixed upstream, in a later stable release.

Component: symbolics

Author: Ralf Stephan

Reviewer: Paul Masson

Issue created by migration from https://trac.sagemath.org/ticket/19775

[rwst]

Upstream: Reported upstream. Developers acknowledge bug.

[rwst]

comment:4

Fixed in pynac-0.6.8.

[rwst]

Changed upstream from Reported upstream. Developers acknowledge bug. to Fixed upstream, in a later stable release.

[paulmasson]

Dependencies: #21034

[paulmasson]

Reviewer: Paul Masson

[paulmasson]

comment:6

Fixed in #21034

[paulmasson]

Author: Ralf Stephan