Differences between revisions 1 and 14 (spanning 13 versions)

Sage 9.4 Release Tour

current development cycle (2021)

Contents

Sage 9.4 Release Tour

Goals and tickets

Add support for gcc 11
Add support for macOS Big Sur that does not depend on homebrew's gcc@10
packages upgrades
- - https://repology.org/projects/?inrepo=sagemath_develop - many upgrades enabled by dropping support for Python 3.6
Drop support for optional packages with system gcc 4.x
Open Meta-Tickets
Trac tickets with milestone 9.4

Symbolics

Extended interface with SymPy

The SymPy package has been updated to version 1.8.

SageMath has a bidirectional interface with SymPy. Symbolic expressions in Sage provide a _sympy_ method, which converts to SymPy; also, Sage attaches _sage_ methods to various SymPy classes, which provide the opposite conversion.

In Sage 9.4, several conversions have been added. Now there is a bidirectional interface as well for matrices and vectors. #31942

sage: M = matrix([[sin(x), cos(x)], [-cos(x), sin(x)]]); M
[ sin(x)  cos(x)]
[-cos(x)  sin(x)]
sage: sM = M._sympy_(); sM
Matrix([
[ sin(x), cos(x)],
[-cos(x), sin(x)]])
sage: sM.subs(x, pi/4)           # computation in SymPy
Matrix([
[ sqrt(2)/2, sqrt(2)/2],
[-sqrt(2)/2, sqrt(2)/2]])

Work is underway to make SymPy's symbolic linear algebra methods available in Sage via this route.

Sage has added a formal set membership function element_of for use in symbolic expressions; it converts to a SymPy's Contains expression. #24171

Moreover, all sets and algebraic structures (Parents) of SageMath are now accessible to SymPy by way of a wrapper class, which implements the SymPy Set API. #31938

sage: F = Family([2, 3, 5, 7]); F
Family (2, 3, 5, 7)
sage: sF = F._sympy_(); sF
SageSet(Family (2, 3, 5, 7))          # this is how the wrapper prints
sage: sF._sage_() is F
True                                  # bidirectional
sage: bool(sF)
True
sage: len(sF)
4
sage: sF.is_finite_set                # SymPy property
True

Finite or infinite, we can wrap it:

sage: W = WeylGroup(["A",1,1])
sage: sW = W._sympy_(); sW
SageSet(Weyl Group of type ['A', 1, 1] (as a matrix group acting on the root space))
sage: sW.is_finite_set
False
sage: sW.is_iterable
True
sage: sB3 = WeylGroup(["B", 3])._sympy_(); sB3
SageSet(Weyl Group of type ['B', 3] (as a matrix group acting on the ambient space))
sage: len(sB3)
48

Some parents or constructions have a more specific conversion to SymPy #31931.

sage: ZZ3 = cartesian_product([ZZ, ZZ, ZZ])
sage: sZZ3 = ZZ3._sympy_(); sZZ3
ProductSet(Integers, Integers, Integers)
sage: (1, 2, 3) in sZZ3

sage: NN = NonNegativeIntegers()
sage: NN._sympy_()
Naturals0

sage: (RealSet(1, 2).union(RealSet.closed(3, 4)))._sympy_()
Union(Interval.open(1, 2), Interval(3, 4))

See Meta-ticket #31926: Connect Sage sets to SymPy sets

Convex geometry

ABC for convex sets

Sage 9.4 has added an abstract base class ConvexSet_base (as well as abstract subclasses ConvexSet_closed, ConvexSet_compact, ConvexSet_relatively_open, ConvexSet_open) for convex subsets of finite-dimensional vector spaces. The abstract methods and default implementations of methods provide a unifying API to the existing classes Polyhedron_base, ConvexRationalPolyhedralCone, LatticePolytope, and PolyhedronFace. #31919, #31959, #31990

As part of the API, there are new methods for point-set topology such as is_open, relative_interior, and closure. For example, taking the relative_interior of a polyhedron constructs an instance of RelativeInterior, a simple object that provides a __contains__ method and all other methods of the ConvexSet_base API. #31916

sage: P = Polyhedron(vertices=[(1,0), (-1,0)])
sage: ri_P = P.relative_interior(); ri_P
Relative interior of
 a 1-dimensional polyhedron in ZZ^2 defined as the convex hull of 2 vertices
sage: (0, 0) in ri_P
True
sage: (1, 0) in ri_P
False

Polyhedral geometry

Manifolds

Configuration changes

Support for system Python 3.6 dropped

It was already deprecated in Sage 9.3. #30551

It is still possible to build the Sage distribution on systems with old Python versions, but Sage will build its own copy of Python 3.9.x in this case.

./configure --prefix=SAGE_LOCAL --with-sage-venv=SAGE_VENV

#29013

Package upgrades

Availability of Sage 9.4 and installation help

The first beta of the 9.4 series, 9.4.beta0, was tagged on 2021-05-26.

See sage-devel for development discussions and sage-release for announcements of beta versions and release candidates.

-  ⇤ ← Revision 1 as of 2021-03-26 20:35:47 → 
  Size: 903
  Editor: mkoeppe
  Comment: prep 9.4
+   ← Revision 14 as of 2021-07-20 03:26:22 → ⇥
  Size: 5851
  Editor: mkoeppe
  Comment: remove py 3.10
-Deletions are marked like this.
+Additions are marked like this.
 Line 3:
-not started yet (2021)
+current development cycle (2021)
 Line 7:
-== Tickets ==
+== Goals and tickets ==

 * Add support for gcc 11

 * Add support for macOS Big Sur that does not depend on homebrew's gcc@10

 * packages upgrades 
   - https://repology.org/projects/?inrepo=sagemath_develop
   - many upgrades enabled by dropping support for Python 3.6

 * Drop support for optional packages with system gcc 4.x
-Line 13:
+Line 23:
+== Symbolics ==

=== Extended interface with SymPy ===

The [[https://www.sympy.org/en/index.html|SymPy]] package has been updated to version 1.8.

!SageMath has a bidirectional interface with !SymPy. Symbolic expressions in Sage provide a `_sympy_` method, which converts to !SymPy; also, Sage attaches `_sage_` methods to various !SymPy classes, which provide the opposite conversion.

In Sage 9.4, several conversions have been added. Now there is a bidirectional interface as well for 
matrices and vectors. [[https://trac.sagemath.org/ticket/31942|#31942]]
{{{
sage: M = matrix([[sin(x), cos(x)], [-cos(x), sin(x)]]); M
[ sin(x)  cos(x)]
[-cos(x)  sin(x)]
sage: sM = M._sympy_(); sM
Matrix([
[ sin(x), cos(x)],
[-cos(x), sin(x)]])
sage: sM.subs(x, pi/4)           # computation in SymPy
Matrix([
[ sqrt(2)/2, sqrt(2)/2],
[-sqrt(2)/2, sqrt(2)/2]])
}}}
Work is underway to make !SymPy's symbolic linear algebra methods available in Sage via this route.

Sage has added a formal set membership function `element_of` for use in symbolic expressions; it converts to a !SymPy's `Contains` expression. [[https://trac.sagemath.org/ticket/24171|#24171]]

Moreover, all sets and algebraic structures (`Parent`s) of !SageMath are now accessible to !SymPy by way of a wrapper class, which implements the [[https://docs.sympy.org/latest/modules/sets.html#set|SymPy Set API]]. [[https://trac.sagemath.org/ticket/31938|#31938]]
{{{
sage: F = Family([2, 3, 5, 7]); F
Family (2, 3, 5, 7)
sage: sF = F._sympy_(); sF
SageSet(Family (2, 3, 5, 7))          # this is how the wrapper prints
sage: sF._sage_() is F
True                                  # bidirectional
sage: bool(sF)
True
sage: len(sF)
4
sage: sF.is_finite_set                # SymPy property
True
}}}
Finite or infinite, we can wrap it:
{{{
sage: W = WeylGroup(["A",1,1])
sage: sW = W._sympy_(); sW
SageSet(Weyl Group of type ['A', 1, 1] (as a matrix group acting on the root space))
sage: sW.is_finite_set
False
sage: sW.is_iterable
True
sage: sB3 = WeylGroup(["B", 3])._sympy_(); sB3
SageSet(Weyl Group of type ['B', 3] (as a matrix group acting on the ambient space))
sage: len(sB3)
48
}}}
Some parents or constructions have a more specific conversion to !SymPy [[https://trac.sagemath.org/ticket/31931|#31931]].
{{{
sage: ZZ3 = cartesian_product([ZZ, ZZ, ZZ])
sage: sZZ3 = ZZ3._sympy_(); sZZ3
ProductSet(Integers, Integers, Integers)
sage: (1, 2, 3) in sZZ3

sage: NN = NonNegativeIntegers()
sage: NN._sympy_()
Naturals0

sage: (RealSet(1, 2).union(RealSet.closed(3, 4)))._sympy_()
Union(Interval.open(1, 2), Interval(3, 4))
}}}
See [[https://trac.sagemath.org/ticket/31926|Meta-ticket #31926: Connect Sage sets to SymPy sets]]

== Convex geometry ==

=== ABC for convex sets ===

Sage 9.4 has added an abstract base class `ConvexSet_base` (as well as abstract subclasses `ConvexSet_closed`, `ConvexSet_compact`, `ConvexSet_relatively_open`, `ConvexSet_open`) for convex subsets of finite-dimensional vector spaces.  The abstract methods and default implementations of methods provide a unifying API to the existing classes `Polyhedron_base`, `ConvexRationalPolyhedralCone`, `LatticePolytope`, and `PolyhedronFace`. [[https://trac.sagemath.org/ticket/31919|#31919]], [[https://trac.sagemath.org/ticket/31959|#31959]], [[https://trac.sagemath.org/ticket/31990|#31990]]

As part of the API, there are new methods for point-set topology such as `is_open`, `relative_interior`, and `closure`.  For example, taking the `relative_interior` of a polyhedron constructs an instance of `RelativeInterior`, a simple object that provides a `__contains__` method and all other methods of the `ConvexSet_base` API. [[https://trac.sagemath.org/ticket/31916|#31916]]
{{{
sage: P = Polyhedron(vertices=[(1,0), (-1,0)])
sage: ri_P = P.relative_interior(); ri_P
Relative interior of
 a 1-dimensional polyhedron in ZZ^2 defined as the convex hull of 2 vertices
sage: (0, 0) in ri_P
True
sage: (1, 0) in ri_P
False
}}}

=== Polyhedral geometry ===


== Manifolds ==


== Configuration changes ==

=== Support for system Python 3.6 dropped ===

It was already deprecated in Sage 9.3. [[https://trac.sagemath.org/ticket/30551|#30551]]

It is still possible to build the Sage distribution on systems with old Python versions, but Sage will build its own copy of Python 3.9.x in this case.

=== ./configure --prefix=SAGE_LOCAL --with-sage-venv=SAGE_VENV ===

[[https://trac.sagemath.org/ticket/29013|#29013]]


== Package upgrades ==
-Line 15:
+Line 139:
-The 9.4 series has not been started yet.
+The first beta of the 9.4 series, 9.4.beta0, was tagged on 2021-05-26.

Diff for "ReleaseTours/sage-9.4"