This release fixes troubles with gcc-9.1 see #27676

Tarball:

[https://github.com/BRiAl/BRiAl/releases/download/1.2.5/brial-1.2.5.tar.
bz2]

URL: https://trac.sagemath.org/27942
Reported by: fbissey
Ticket author(s): François Bissey
Reviewer(s): Volker Braun

Pickling does not work correctly for codes:

{{{
sage: C = codes.HammingCode(GF(2), 3)
sage: C.decoders_available()
['InformationSet', 'NearestNeighbor', 'Syndrome']
sage: save(C, 'obj')
}}}

but in a fresh sage run,

{{{
sage: D = load('obj')
sage: D.decoders_available()
[]
}}}

URL: https://trac.sagemath.org/27890
Reported by: klee
Ticket author(s): Kwankyu Lee
Reviewer(s): Vincent Delecroix

By not running over the full reflection group..

URL: https://trac.sagemath.org/27924
Reported by: chapoton
Ticket author(s): Frédéric Chapoton, Christian Stump
Reviewer(s): Christian Stump, Frédéric Chapoton

get rid of one import from sagenb

URL: https://trac.sagemath.org/27530
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): John Palmieri

Some basic ideal operations are unsupported when `QQbar` is the base
field:

{{{
sage: R.<x,y,z> = QQbar[]

sage: I = ideal(x,z)
sage: J = ideal(R(1))
}}}

Now, both quotient and saturation:

{{{
sage: I.quotient(J)
sage: I.saturation(J)
}}}

fail with almost the same error message:

{{{
TypeError: Cannot call Singular function 'quotient' with ring parameter
of type '<class 'sage.rings.polynomial.multi_polynomial_ring.MPolynomial
Ring_polydict_domain_with_category'>'
}}}

Singular can perform these operations, but first we have to convert to a
!NumberField.

{{{
sage: S.<a> = QQ[]
sage: NFa = NumberField(a^4+1, 'a')

sage: R.<x,y,z> = NFa[]

sage: I = ideal(x,z)
sage: J = ideal(R(1))

sage: I.quotient(J)
Ideal (z, x) of Multivariate Polynomial Ring in x, y, z over Number
Field in a with defining polynomial a^4 + 1
}}}

The conversion just needs to be done automatically.

URL: https://trac.sagemath.org/25351
Reported by: gh-BrentBaccala
Ticket author(s): Brent Baccala
Reviewer(s): Vincent Delecroix

In cases where Fricas gives back an unsolved integral:
{{{
sage: integrate(abs(x), x, algorithm='fricas')
...
ValueError: Unable to parse: integral(abs(x),x::Symbol)
}}}

URL: https://trac.sagemath.org/17908
Reported by: rws
Ticket author(s): Martin Rubey
Reviewer(s): Frédéric Chapoton

Fix combinat.set_partition_ordered doctest for python3

URL: https://trac.sagemath.org/27930
Reported by: vklein
Ticket author(s): Vincent Klein
Reviewer(s): Frédéric Chapoton

The ticket  #27607 introduced a regression: function field divisors are
not hashable anymore!

As of sage 8.8.beta7:
{{{
sage: K.<x> = FunctionField(GF(2)); R.<t> = K[]
sage: L.<y> = K.extension(t^3 + x^3*t + x)
sage: f = x/(y+1)
sage: f.divisor()
- Place (1/x, 1/x^3*y^2 + 1/x)
 + Place (1/x, 1/x^3*y^2 + 1/x^2*y + 1)
 + 3*Place (x, y)
 - Place (x^3 + x + 1, y + 1)
sage: d = _
sage: {d: 1}
------------------------------------------------------------------------
---
TypeError                                 Traceback (most recent call
last)
...
TypeError: <class 'sage.rings.function_field.divisor.DivisorGroup
_with_category.element_class'> is not hashable

}}}

URL: https://trac.sagemath.org/27935
Reported by: klee
Ticket author(s): Kwankyu Lee
Reviewer(s): Travis Scrimshaw

also fixing one lgtm warning about unused variable

URL: https://trac.sagemath.org/27927
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): Travis Scrimshaw

some pep, pyflakes, lgtm fixes

URL: https://trac.sagemath.org/27922
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): John Palmieri

some pep, pyflakes, lgtm suggestions

URL: https://trac.sagemath.org/27918
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): Travis Scrimshaw

The dynamics code was relocated from schemes to dynamical systems in
#23497 in Aug 2017. This ticket is to remove the deprecation warnings
and functions that were left in place in schemes.

URL: https://trac.sagemath.org/27900
Reported by: bhutz
Ticket author(s): Ben Hutz
Reviewer(s): Travis Scrimshaw

Zero is not necessary here:
{{{
sage: K.<x> = FunctionField(GF(2)); _.<Y> = K[]
sage: F.<y> = K.extension(Y)
sage: p, = F.places_infinite()
sage: p.prime_ideal().gens_two()
(1/x, 0)
}}}

URL: https://trac.sagemath.org/27850
Reported by: klee
Ticket author(s): Kwankyu Lee
Reviewer(s): Frédéric Chapoton

Several methods for elements in the new function field code (Trac
#22982) can be profitably moved to the `FunctionFieldElement`
superclass:

- divisor, divisor_of_zeros, divisor_of_poles, zeros, and poles

URL: https://trac.sagemath.org/26991
Reported by: gh-BrentBaccala
Ticket author(s): Brent Baccala
Reviewer(s): Travis Scrimshaw

{{{
sage: LazyPowerSeriesRing(QQ, 'z').gen()
}}}
gives an error.

URL: https://trac.sagemath.org/27931
Reported by: dkrenn
Ticket author(s): Daniel Krenn
Reviewer(s): Travis Scrimshaw

so that
{{{
gap3._eval_line('LoadPackage("{}");'.format('chevie'))
}}}
works

URL: https://trac.sagemath.org/27925
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): Christian Stump

Trac #27920: Upgrade pynormaliz to 2.7 to fix installation error when a 'configure' script is accessible in PATH

As reported in #27731 and https://groups.google.com/d/msg/sage-
devel/2virhaHdt1k/nK-AtlByBAAJ . This is fixed by upgrading !PyNormaliz
to version 2.7.

upstream tarball

    https://files.pythonhosted.org/packages/b3/2a/6bf3717ff75f4b6dd8cbcb
a3dffdf75e65162c7aaad4ff95a64b4a768e7e/PyNormaliz-2.7.tar.gz

URL: https://trac.sagemath.org/27920
Reported by: mkoeppe
Ticket author(s): Matthias Koeppe
Reviewer(s): Vincent Delecroix

fix some pep, pyflakes, lgtm suggestions there

URL: https://trac.sagemath.org/27919
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): John Palmieri

The recent GAP `PackageManager` package makes it much much easier to
install new GAP packages. It seems to work smoothly from within Sage (up
to the caveat of #27911), with e.g.:
{{{
    sage: libgap.InstallPackage("Semigroups")
}}}

So this seems like a valuable low hanging fruit.

Of course, the user still needs to have compiler tools and write access
to the Sage install; but there is only so much we can do.

https://www.gap-system.org/Packages/packagemanager.html

URL: https://trac.sagemath.org/27912
Reported by: nthiery
Ticket author(s): Nicolas M. Thiéry
Reviewer(s): Dima Pasechnik

This ticket adds a small downward-pointing arrow to the lower right-hand
corner of each generated Three.js scene. When it is clicked a screenshot
is saved to the browser-dependent downloads directory. There does not
appear to be a way to allow the user to specify where the file will
download due to browser security issues.

This ticket includes a bit of added white space to make the template a
bit more legible.

URL: https://trac.sagemath.org/27910
Reported by: paulmasson
Ticket author(s): Paul Masson
Reviewer(s): Eric Gourgoulhon

While porting some code from `sage.libs.ppl` to `pplpy`, I encountered
the following.
{{{
sage: K.<f> = QQ[]
sage: 1.__mpz__() * f
RuntimeError                              Traceback (most recent call
last)
...
RuntimeError: There is a BUG in the coercion model:
                Action found for R <built-in function mul> S does not
have the correct domains
                R = Set of Python objects of class 'mpz'
                S = Univariate Polynomial Ring in f over Rational Field
                (should be Integer Ring, Univariate Polynomial Ring in f
over Rational Field)
                action = Left scalar multiplication by Integer Ring on
Univariate Polynomial Ring in f over Rational Field (<type
'sage.categories.action.PrecomposedAction'>)
}}}

URL: https://trac.sagemath.org/27893
Reported by: mkoeppe
Ticket author(s): Vincent Klein
Reviewer(s): Vincent Delecroix

The current `is_simplicial` method returns `False` if the polytope is
not full-dimensional.

{{{
sage: P = polytopes.simplex()
sage: P
A 3-dimensional polyhedron in ZZ^4 defined as the convex hull of 4
vertices
sage: P.is_simplicial()
False
sage: P.affine_hull().is_simplicial()
True
}}}

URL: https://trac.sagemath.org/27700
Reported by: gh-LaisRast
Ticket author(s): Laith Rastanawi
Reviewer(s): Jean-Philippe Labbé

{{{
sage: G = GL(2,5)
sage: g = G( matrix([[1,0],[0,4]]))
sage: H = G.subgroup([g])
sage: g in H
False
}}}
Note that
{{{
sage: g.gap() in H.gap()
True
}}}
The underlying reason should be
{{{
sage: G.has_coerce_map_from(H)
False
}}}

URL: https://trac.sagemath.org/27468
Reported by: sbrandhorst
Ticket author(s): Simon Brandhorst
Reviewer(s): Travis Scrimshaw

{{{
wget -O upstream/openblas-0.3.6.tar.gz
https://github.com/xianyi/OpenBLAS/archive/v0.3.6.tar.gz
}}}

URL: https://trac.sagemath.org/27847
Reported by: vbraun
Ticket author(s): Volker Braun
Reviewer(s): Dima Pasechnik, Matthias Koeppe

often in the doc, sometimes in the code

URL: https://trac.sagemath.org/27906
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): John Palmieri

URL: https://trac.sagemath.org/27903
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): John Palmieri

Make SortedDirectoryWalkerABC test suite pass when the source is not
available and SAGE_SRC==SAGE_LIB, such as in distro packages.

URL: https://trac.sagemath.org/27915
Reported by: arojas
Ticket author(s): Antonio Rojas
Reviewer(s): François Bissey

This ticket adjusts the hash of multivariate Laurent polynomials, so
that it agrees with the hash of univariate Laurent polynomials.

This solves the following problem: Using Python 3, this doctest in
`laurent_polynomial.pyx` fails about 1 out of 4 times.
{{{
            sage: L.<w,z> = LaurentPolynomialRing(QQ)
            sage: len({hash(w^i*z^j) for i in [-2..2] for j in [-2..2]})
            25
}}}
Due to hash collisions, the result can be smaller than 25 (such as 23 or
21). This gets even worse when using a larger range of monomials.

Regardless of that, it is desirable that univariate and multivariate
Laurent polynomials have the same hash anyway. The univariate hash
implementation does not seem to have these collisions, so adopting that
implementation solves this problem.

For reference, the univariate and multivariate hashes were implemented
in #21272 and #23864.

URL: https://trac.sagemath.org/27914
Reported by: gh-mwageringel
Ticket author(s): Markus Wageringel
Reviewer(s): Frédéric Chapoton