Upgrade to Pynac-0.6.5

[rwst]

That Pynac version has:

• fix for: assume(x>0) sets integer flag (assume(x>0) sets integer flag #20456)
• fix Maxima crashes by implementing fast Hermite (ECL crash with Hermite polynomials #20297) and Gegenbauer (crash with ultraspherical polynomials #20428) polynomials in Pynac
• some fixes to handling of elements of rings with positive characteristics (properties of converted finite field elements are wrong #20162)
• Python 3 build fix
• automatic trigonometric and log simplifications

https://github.com/pynac/pynac/releases/download/pynac-0.6.5/pynac-0.6.5.tar.bz2

Depends on #20312

Component: packages: standard

Author: Ralf Stephan, Benjamin Hackl, Aaditya Thakkar

Branch/Commit: 72d96a5

Reviewer: Eric Gourgoulhon, Volker Braun

Issue created by migration from https://trac.sagemath.org/ticket/20475

[rwst]

Branch: u/rws/upgrade_to_pynac_0_6_5

[rwst]

Author: Ralf Stephan, Benjamin Hackl, Aaditya Thakkar

[rwst]

New commits:

39b85b0	new version/chksum
11e2b78	doctest changes and a few fixes in support of pynac-0.6.5

[rwst]

Commit: 11e2b78

[jdemeyer]

comment:3

I consider this a bug:

         sage: S.<y> = PolynomialRing(RR)
         sage: hermite(3,y)
         8*y^3 - 12*y

[jdemeyer]

comment:4

Does Sage use Ginac for other polynomial functions?

[rwst]

Dependencies: #20312

[rwst]

comment:5

Replying to @jdemeyer:

I consider this a bug:

         sage: S.<y> = PolynomialRing(RR)
         sage: hermite(3,y)
         8*y^3 - 12*y

Indeed, see #20312.

Does Sage use Ginac for other polynomial functions?

No. So?