SymPy 0.7.0 Released

[Aaron Meurer]

Hi everyone. After more than a year, we're finally releasing SymPy 0.7.0.

You can get the source (for Linux/Mac OS X) at
http://code.google.com/p/sympy/downloads/detail?name=sympy-0.7.0.tar.gz
and the Windows installer at
http://code.google.com/p/sympy/downloads/detail?name=sympy-0.7.0.win32.exe.
You can download the docs for this release at
http://code.google.com/p/sympy/downloads/detail?name=sympy-0.7.0-docs-html.zip.

The change log and list of contributors for this release is at
https://github.com/sympy/sympy/wiki/Release-Notes-for-0.7.0, which
I've included at the bottom of this email.

Tomorrow, I will update all the relevant webpages, and also merge the
0.7.0 branch back into master.

I want to thank everyone who contributed to this release. We had 64
people contribute to this release, 37 of whom contributed for the
first time since the last release. That's over half of the
contributors! See below for a full list of people who contributed to
this release.

Aaron Meurer

# Release Notes for SymPy 0.7.0
These are the release notes for SymPy 0.7.0.

## Backwards compatibility breaks

* This will be the last release of SymPy to support Python 2.4.
Dropping support for Python 2.4 will let us move forward with things
like supporting Python 3, and will let us use things that were
introduced in Python 2.5, like with-statement context managers.
* no longer support creating matrices without brackets (see: issue 930)
* Renamed `sum()` to `summation()` (see: 3e763a8, issues 1376, 1727).
This was changed so that it no longer overrides the built-in `sum()`.
The unevaluated summation is still called `Sum()`.
* Renamed `abs()` to `Abs()` (see: 64a12a4, issue 1727). This was
also changed so that it no longer overrides the built-in `abs()`. Note
that because of `__abs__` magic, you can still do `abs(expr)` with the
built-in `abs()`, and it will return `Abs(expr)`.
* Renamed `max_()` and `min_()` to now `Max()` and `Min()` (see:
99a271e, issue 2153)
* Changed behaviour of `symbols()`. `symbols('xyz')` gives now a
single symbol (`'xyz'`), not three (`'x'`, `'y'` and `'z'`) (see:
f6452a8). Use `symbols('x,y,z')` or `symbols('x y z')` to get three
symbols. The 'each_char' option will still work but is being
deprecated.
* Split class `Basic` into new classes `Expr`, `Boolean` (see:
a0ab479, 635d89c). Classes that are designed to be part of standard
symbolic expressions (like `x**2*sin(x)`) should subclass from `Expr`.
More generic objects that do not work in symbolic expressions but
still want the basic SymPy structure like `.args` and basic methods
like `.subs()` should only subclass from `Basic`.
* `as_basic()` method was renamed to `as_expr()` to reflect changes in
the core (see: e61819d, 80dfe91)
* Methods `as_coeff_terms` and `as_coeff_factors` were renamed to
`as_coeff_mul` and `as_coeff_add`, respectively.
* Removed the `trim()` function. The function is redundant with the
new polys (see below). Use the `cancel()` function instead.

## Major Changes
### Polys

* New internal representations of dense and sparse polynomials (see:
6aecdb7, 31c9aa4)
* Implemented algorithms for real and complex root isolation and
counting (see: 3acac67, 4b75dae, fa1206e, 103b928, 45c9b22, 8870c8b,
b348b30)
* Improved Gröbner bases algorithm (see: ff65e9f, 891e4de, 310a585)
* Field isomorphism algorithm (see: b097b01, 08482bf)
* Implemented efficient orthogonal polynomials (see: b8fbd59)
* Added configuration framework for polys (see: 33d8cdb, 7eb81c9)
* Function for computing minimal polynomials (see: 88bf187, f800f95)
* Function for generating Viete's formulas (see: 1027408)
* `roots()` supports more classes of polynomials (e.g. cyclotomic)
(see: d8c8768, 75c8d2d)
* Added a function for recognizing cyclotomic polynomials (see: b9c2a9a)
* Added a function for computing Horner form of polynomials (see: 8d235c7)
* Added a function for computing symmetric reductions of polynomials
(see: 6d560f3)
* Added generators of Swinnerton-Dyer, cyclotomic, symmetric, random
and interpolating polynomials (see: dad03dd, 6ccf20c, dc728d6,
2f17684, 3004db8)
* Added a function computing isolation intervals of algebraic numbers
(see: 37a58f1)
* Polynomial division (`div()`, `rem()`, `quo()`) now defaults to a
field (see: a72d188)
* Added wrappers for numerical root finding algorithms (see: 0d98945, f638fcf)
* Added symbolic capabilities to `factor()`, `sqf()` and related
functions (see: d521c7f, 548120b, f6f74e6, b1c49cd, 3527b64)
* `together()` was significantly improved (see: dc327fe)
* Added support for iterable containers to `gcd()` and `lcm()` (see: e920870)
* Added a function for constructing domains from coefficient
containers (see: a8f20e6)
* Implemented greatest factorial factorization (see: d4dbbb5)
* Added partial fraction decomposition algorithm based on
undetermined coefficient approach (see: 9769d49, 496f08f)
* `RootOf` and `RootSum` were significantly improved (see: f3e432,
4c88be6, 41502d7)
* Added support for gmpy (GNU Multiple Precision Arithmetic Library)
(see: 38e1683)
* Allow to compile `sympy.polys` with Cython (see: afb3886)
* Improved configuration of variables in `Poly` (see: 22c4061)
* Added documentation based on Wester's examples (see: 1c23792)
* Irreducibility testing over finite fields (see: 17e8f1f)
* Allow symmetric and non-symmetric representations over finite
fields (see: 60fbff4)
* More consistent factorization forms from `factor()` and `sqf()`
(see: 5df77f5)
* Added support for automatic recognition algebraic extensions (see: 7de602c)
* Implemented Collins' modular algorithm for computing resultants
(see: 950969b)
* Implemented Berlekamp's algorithm for factorization over finite
fields (see: 70353e9)
* Implemented Trager's algorithm for factorization over algebraic
number fields (see: bd0be06)
* Improved Wang's algorithm for efficient factorization of
multivariate polynomials (see: 425e225)

### Quantum

* Symbolic, abstract dirac notation in `sympy.physics.quantum`. This
includes operators,
states (bras and kets), commutators, anticommutators, dagger, inner
products, outer
products, tensor products and Hilbert spaces
* Symbolic quantum computing framework that is based on the general
capabilities in
`sympy.physics.quantum`. This includes qubits
(`sympy.physics.quantum.qubit`), gates
(`sympy.physics.quantum.gate`), Grover's algorithm
(`sympy.physics.quantum.grover`),
the quantum Fourier transform (`sympy.physics.quantum.qft`), Shor's algorithm
(`sympy.physics.quantum.shor`) and circuit plotting
(`sympy.physics.quantum.circuitplot`)
* Second quantization framework that inclues creation/anihilation operators for
both Fermions and Bosons and Wick's theorem for Fermions
(`sympy.physics.secondquant`).
* Symbolic quantum angular momentum (spin) algebra
(`sympy.physics.quantum.spin`)
* Hydrogen wave functions (Schroedinger) and energies (both
Schroedinger and Dirac)
* Wave functions and energies for 1D harmonic oscillator
* Wave functions and energies for 3D spherically symmetric harmonic oscillator
* Wigner and Clebsch Gordan coefficients

## Everything else

* Implement symarray, providing numpy nd-arrays of symbols.
* update mpmath to 0.16
* Add a tensor module (see:
[[http://code.google.com/p/sympy/wiki/CodeGenerationReport]])
* A lot of stuff was being imported with `from sympy import *` that
shouldn't have been (like `sys`). This has been fixed.

### Assumptions:
* Refine
* Added predicates (see: 7c0b857, 53f0e1a, d1dd6a3..)
* Added query handlers for algebraic numbers (see: f3bee7a)
* Implement a SAT solver (see:
[[http://code.google.com/p/sympy/wiki/SuperchargingAssumptionsReport]],
2d96329, acfbe75, etc.)

### Concrete
* Finalized implementation of Gosper's algorithm (see: 0f187e5, 5888024)
* Removed redundant `Sum2` and related classes (see: ef1f6a7)

### Core:
* Split `Atom` into `Atom` and `AtomicExpr` (see: 965aa91)
* Various `sympify()` improvements
* Added functionality for action verbs (many functions can be called
both as global functions and as methods e.g. `a.simplify() ==
simplify(a)`)
* Improve handling of rational strings (see: 053a045, issue 1778)
* Major changes to factoring of integers (see: 273f450, issue 2003)
* Optimized `.has()` (see: c83c9b0, issue 1980; d86d08f)
* Improvements to power (see: c8661ef, issue 1963)
* Added range and lexicographic syntax to `symbols()` and `var()`
(see: f6452a8, 9aeb220, 957745a)
* Added `modulus` argument to `expand()` (see: 1ea5be8)
* Allow to convert `Interval` to relational form (see: 4c269fe)
* SymPy won't manipulate minus sign of expressions any more (see:
6a26941, 9c6bf0f, e9f4a0a)
* `Real` and `.is_Real` were renamed to `Float` and `.is_Float`.
`Real` and `.is_Real` still remain as deprecated shortcuts to `Float`
and `is_Float` for backwards compatibility. (see: abe1c49)

### Geometry:
* Various improvements to Ellipse
* Updated documentation to numpy standard
* Polygon and Line improvements
* Allow all geometry objects to accept a tuple as `Point` args

### Integrals:
* Various improvements (see eg. issues 1772, 1999, 1992, 1987.. etc)

### isympy
* Fixed the `-p` switch (see: e8cb04a)
* Caching can be disabled using `-C` switch (see: 0d8d748)
* Ground types can be set using `-t` switch (see: 75734f8)
* Printing ordering can be set using `-o` switch (see: fcc6b13, 4ec9dc5)

### Logic
* implies object adheres to negative normal form
* Create new boolean class, `logic.boolalg.Boolean`
* Added XOR operator (^) support
* Added If-then-else (ITE) support
* Added the dpll algorithm

### Functions:
* Added Piecewise, B-splines
* Spherical Bessel function of the second kind implemented
* Add series expansions of multivariate functions (see: d4d351d)

### Matrices:
* Add elementwise product (Hadamard product)
* Extended QR factorization for general full ranked mxn matrices
* Remove deprecated functions `zero()`, `zeronm()`, `one()` (see: 5da0884)
* Added cholesky and LDL factorizations, and respective solves.
* Added functions for efficient triangular and diagonal solves.
* `SMatrix` was renamed to `SparseMatrix` (see: acd1685)

### Physics
* See the Quantum section

### Printing:
* Implemented pretty printing of binomials (see: 58c1dad)
* Implemented pretty printing of Sum() (see: 84f2c22, 95b4321)
* `sympy.printing` now supports ordering of terms and factors (see: 859bb33)
* Lexicographic order is now the default. Now finally things will
print as `x**2 + x + 1` instead of `1 + x + x**2`, however series
still print using reversed ordering, e.g. `x - x**3/6 + O(x**5)`. You
can get the old order (and other orderings) by setting the `-o` option
to isympy (see: 08b4932, a30c5a3)

### Series:
* Implement a function to calculate residues, `residue()`
* Implement nseries and lseries to handle `x0 != 0`, series should be
more robust now (see: 2c99999, issues 2122-2124)
* Improvements to Gruntz algorithm

### Simplify:
* Added `use()` (see: 147c142)
* `ratsimp()` now uses `cancel()` and `reduced()` (see: 108fb41)
* Implemented EPath (see: 696139d, bf90689)

### Solvers:
* ODE improvements (see: d12a2aa, 3542041; 73fb9ac)
* Added support for solving inequalities (see: 328eaba, 8455147, f8fcaa7)

### Utilities:
* Improve cartes, for generating the Cartesian product (see: b1b10ed)
* Added a function computing topological sort of graphs (see: b2ce27b)
* Allow to setup a customized printer in `lambdify()` (see: c1ad905)
* `flatten()` was significantly improved (see: 31ed8d7)
* Major improvements to the Fortran code generator (see:
[[http://code.google.com/p/sympy/wiki/CodeGenerationReport]], 3383aa3,
7ab2da2, etc.)

In addition to the more noticeable changes listed above, there have
been numerous other smaller additions, improvements and bug fixes in
the ~2000 commits in this release. See the git log for a full list of
all changes. The command `git log sympy-0.6.7..sympy-0.7.0` will show
all commits made between this release and the last. You can also see
the issues closed since the last release
[here](http://code.google.com/p/sympy/issues/list?can=1&q=closed-after%3A2010%2F3%2F17+closed-before%3A2011%2F6%2F13&sort=-closed&colspec=ID+Type+Status+Priority+Milestone+Owner+Summary+Stars+Closed&cells=tiles).

## Authors

The following people contributed at least one patch to this release
(names are given in alphabetical order by last name). A total of 64
people contributed to this release. People with a * by their names
contributed a patch for the first time for this release. Thirty-seven
people contributed for the first time for this release. Over half of
the people who contributed to this release contributed for the first
time!

Thanks to everyone who contributed to this release!

* Tom Bachmann*
* Tomas Bambas*
* Matthew Brett*
* Ondřej Čertík
* Renato Coutinho
* Addison Cugini*
* Matt Curry*
* Raffaele De Feo*
* Mark Dewing
* Thomas Dixon*
* Harold Erbin
* Pavel Fedotov*
* Gilbert Gede*
* Oleksandr Gituliar*
* Brian Granger
* Alexey U. Gudchenko*
* Øyvind Jensen
* Fredrik Johansson
* Felix Kaiser
* Yuri Karadzhov*
* Gary Kerr*
* Kibeom Kim*
* Nicholas J.S. Kinar*
* Anatolii Koval*
* Sebastian Krämer
* Ryan Krauss
* Gregory Ksionda*
* Priit Laes
* Vladimir Lagunov
* Ronan Lamy
* Tomo Lazovich*
* Saptarshi Mandal*
* David Marek
* Jack McCaffery*
* Benjamin McDonald*
* Aaron Meurer
* Christian Muise*
* Óscar Nájera*
* Jezreel Ng*
* Sherjil Ozair*
* Mateusz Paprocki
* James Pearson
* Fernando Perez
* Vladimir Perić*
* Mario Pernici*
* Nicolas Pourcelot
* rayman*
* Matthew Rocklin*
* Christian Schubert
* Andre de Fortier Smit*
* Chris Smith
* Cristóvão Sousa*
* Akshay Srinivasan
* Vinzent Steinberg
* Prafullkumar P. Tale*
* Andy R. Terrel
* Kazuo Thow*
* Toon Verstraelen
* Sean Vig*
* Luca Weihs*
* Thomas Wiecki
* Shai 'Deshe' Wyborski*
* Jeremias Yehdegho*

[David Joyner]

On Tue, Jun 28, 2011 at 3:37 AM, Aaron Meurer <asme...@gmail.com> wrote:
> Hi everyone.  After more than a year, we're finally releasing SymPy 0.7.0.

Congrads!
How hard would it be to make a new sympy package for Sage?
Here is info on the latest one:
http://www.sagemath.org/packages/standard/sympy-0.6.4.p0.txt

>

...

>
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>

[Vinzent Steinberg]

On Jun 28, 4:40 pm, David Joyner <wdjoy...@gmail.com> wrote:

> On Tue, Jun 28, 2011 at 3:37 AM, Aaron Meurer <asmeu...@gmail.com> wrote:
> > Hi everyone.  After more than a year, we're finally releasing SymPy 0.7.0.
>
> Congrads!
> How hard would it be to make a new sympy package for Sage?
> Here is info on the latest one:http://www.sagemath.org/packages/standard/sympy-0.6.4.p0.txt

I think Ondrej has usually been packaging sympy for sage.

Vinzent

[Fredrik Johansson]

On Tue, Jun 28, 2011 at 9:37 AM, Aaron Meurer <asme...@gmail.com> wrote:
> Hi everyone.  After more than a year, we're finally releasing SymPy 0.7.0.

Congratulations all!

Looks like http://docs.sympy.org hasn't been updated?

Fredrik

[Aaron Meurer]

Yes, as I mentioned in the original email, I haven't updated any of
the websites yet. I plan to do that today, using the list at the
bottom of https://github.com/sympy/sympy/wiki/New-Release as a guide.
If you see anything that's missing there, please add it.

I will also attempt to make Debian and Sage packages. I might need
help with that, though, so any guidance from Ondrej or anyone else who
has experience in that area would be appreciated.

Aaron Meurer

[Aaron Meurer]

OK, I've updated all the webpages, including the docs. All that
remains is to make some packages. Let me know if you see 0.6.7 (or
older) referenced as the latest version anywhere.

Aaron Meurer

[François]

I had a quick look at it. I think it goes down better than sympy-0.6.7, there are a few minor doctests to fix (some answers are now x+2 instead of 2+x) but some code in sage needs adjusting before we ship:

File "/usr/share/sage/devel/sage-main/sage/calculus/test_sympy.py", line 294, in __main__.example_0

Failed example:

    f = e.series(x, Integer(0), Integer(10)); f###line 111:_sage_    >>> f = e.series(x, 0, 10); f

Exception raised:

    Traceback (most recent call last):

      File "/usr/bin/ncadoctest.py", line 1231, in run_one_test

        self.run_one_example(test, example, filename, compileflags)

      File "/usr/bin/sagedoctest.py", line 38, in run_one_example

        OrigDocTestRunner.run_one_example(self, test, example, filename, compileflags)

      File "/usr/bin/ncadoctest.py", line 1172, in run_one_example

        compileflags, 1) in test.globs

      File "<doctest __main__.example_0[43]>", line 1, in <module>

        f = e.series(x, Integer(0), Integer(10)); f###line 111:_sage_    >>> f = e.series(x, 0, 10); f

      File "/usr/lib64/python2.7/site-packages/sympy/core/expr.py", line 1517, in series

        if x0 in [S.Infinity, S.NegativeInfinity]:

      File "integer.pyx", line 850, in sage.rings.integer.Integer.__richcmp__ (sage/rings/integer.c:7498)

      File "element.pyx", line 832, in sage.structure.element.Element._richcmp (sage/structure/element.c:6598)

      File "coerce.pyx", line 889, in sage.structure.coerce.CoercionModel_cache_maps.canonical_coercion (sage/structure/coerce.c:8193)

      File "/usr/lib64/python2.7/site-packages/sympy/core/numbers.py", line 892, in _sage_

        return sage.Integer(self.p)/sage.Integer(self.q)

      File "element.pyx", line 1555, in sage.structure.element.RingElement.__div__ (sage/structure/element.c:12011)

      File "integer.pyx", line 1662, in sage.rings.integer.Integer._div_ (sage/rings/integer.c:11470)

      File "integer_ring.pyx", line 286, in sage.rings.integer_ring.IntegerRing_class._div (sage/rings/integer_ring.c:5167)

    ZeroDivisionError: Rational division by zero

That's the only major problem I detected.

Francois

[Aaron Meurer]

I assume you mean doctests in sage. If you're referring to a doctest
in SymPy, please point it out to us, as to our knowledge there are
none in the release.

And let us know if it's necessary to patch SymPy, so we can fix it upstream.

Oh, and I happen to know that Sage uses symbols(each_char=False)
somewhere in the code. each_char is now False by default, and there
is no need to set it to that. We originally removed this option, but
added it back in as a deprecated feature when I noticed that Sage uses
it. If you want each_char=True, you should replace it with separating
symbols by spaces or commas, like symbols('x y z'). And if you have
any bare symbols('xyz') in the code, with multiple characters and no
each_char, you will need to change that. Also, if you run with python
-Wd, you will see a DeprecationWarning for this.

Aaron Meurer

> --
> You received this message because you are subscribed to the Google Groups
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> To view this discussion on the web visit
> https://groups.google.com/d/msg/sympy/-/G0dzmKE2fBQJ.

[Aaron Meurer]

Oh, and if this version works better in Sage than the previous one,
it's because we actually ran the Sage tests before releasing this time
:) (there were a ton of errors, many existing before the previous
release or two).

Aaron Meurer

[Francois Bissey]

> I assume you mean doctests in sage.  If you're referring to a doctest
> in SymPy, please point it out to us, as to our knowledge there are
> none in the release.
>

I meant in sage. No issue in sympy. sympy-0.6.6 works fine with sage,
0.6.7 doesn't and the stuff that I pasted is the only thing one should worry
about. Of course sage test like:
sage -t -long -force_lib "devel/sage-
main/sage/symbolic/expression_conversions.py"
**********************************************************************
File "/usr/share/sage/devel/sage-
main/sage/symbolic/expression_conversions.py", line 559:
    sage: f._sympy_()
Expected:
    -asin(pi + x)/y + exp(x**2)
Got:
    exp(x**2) - asin(x + pi)/y
**********************************************************************
File "/usr/share/sage/devel/sage-
main/sage/symbolic/expression_conversions.py", line 591:
    sage: s.arithmetic(f, f.operator())
Expected:
    2 + x
Got:
    x + 2
**********************************************************************

should be fixed but they are trivial (notice it is a sage test :) )

> Oh, and I happen to know that Sage uses symbols(each_char=False)
> somewhere in the code.  each_char is now False by default, and there
> is no need to set it to that. We originally removed this option, but
> added it back in as a deprecated feature when I noticed that Sage uses
> it.  If you want each_char=True, you should replace it with separating
> symbols by spaces or commas, like symbols('x y z').  And if you have
> any bare symbols('xyz') in the code, with multiple characters and no
> each_char, you will need to change that. Also, if you run with python
> -Wd, you will see a DeprecationWarning for this.
>

A little grepping turned:
sage/symbolic/expression_conversions.py:        return sympy.symbols(repr(ex),
each_char=False)

as the only location. I'll remember to remove it when we upgrade to 0.7.0,
thanks for the tip.

Francois

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[Aaron Meurer]

By the way, this is because we (finally) changed the default ordering
in the printer to lexicographic (no more "backwards" 2 + x).

Regarding the test failure, it's a little hard to tell what's going on
from the traceback (and with no knowledge of Sage code), but it's
perhaps caused by the fact that we implement infinity as Rational(1,
0). See http://code.google.com/p/sympy/issues/detail?id=281.

Aaron Meurer

> --
> You received this message because you are subscribed to the Google Groups
> "sympy" group.

[Francois Bissey]

> By the way, this is because we (finally) changed the default ordering
> in the printer to lexicographic (no more "backwards" 2 + x).
>
> Regarding the test failure, it's a little hard to tell what's going on
> from the traceback (and with no knowledge of Sage code), but it's
> perhaps caused by the fact that we implement infinity as Rational(1,
> 0).  See http://code.google.com/p/sympy/issues/detail?id=281.
>

That would explain what's going on here. Thank you again for the pointer.
I think we'll have to work on that sage side.

Francois

[Aaron Meurer]

Looking deeper, I think the problem might be with S.NegativeInfinity._sage_:

In [48]: source((-oo)._sage_)
In file: ./sympy/core/numbers.py
def _sage_(self):
import sage.all as sage
#XXX: fixme, this should work:
#return sage.Integer(self[0])/sage.Integer(self[1])
return sage.Integer(self.p)/sage.Integer(self.q)

But oo._sage_ (assumedly) does the right thing:

In [49]: source(oo._sage_)
In file: ./sympy/core/numbers.py
def _sage_(self):
import sage.all as sage
return sage.oo

I'm not sure why the former does not just return -sage.oo. Anyway, I
bet if you patch the SymPy code to do that, it will work (let us know
if it does, so we can fix it here too).

Aaron Meurer

[Francois Bissey]

> Looking deeper, I think the problem might be with
> S.NegativeInfinity._sage_:
>
> In [48]: source((-oo)._sage_)
> In file: ./sympy/core/numbers.py
>     def _sage_(self):
>         import sage.all as sage
>         #XXX: fixme, this should work:
>         #return sage.Integer(self[0])/sage.Integer(self[1])
>         return sage.Integer(self.p)/sage.Integer(self.q)
>
> But oo._sage_ (assumedly) does the right thing:
>
> In [49]: source(oo._sage_)
> In file: ./sympy/core/numbers.py
>     def _sage_(self):
>         import sage.all as sage
>         return sage.oo
>
> I'm not sure why the former does not just return -sage.oo.  Anyway, I
> bet if you patch the SymPy code to do that, it will work (let us know
> if it does, so we can fix it here too).
>

I think I found it:
class Infinity(RationalConstant):
    __metaclass__ = Singleton

defines

    def _sage_(self):
        import sage.all as sage
        return sage.oo

But:
class NegativeInfinity(RationalConstant):
    __metaclass__ = Singleton

doesn't have an equivalent statement for _sage_ so I guess this bit is used:
    p = -1
    q = 0

I'll add a sage bit in there and see if it fixes the problem.

Francois

[Aaron Meurer]

Oh, you're right. That first code snippet is Rational._sage_. So
yes, you should just define NegativeInfinity._sage_, and it should
hopefully work.

Aaron Meurer

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[Francois Bissey]

> I think I found it:
> class Infinity(RationalConstant):
>     __metaclass__ = Singleton
>
> defines
>     def _sage_(self):
>         import sage.all as sage
>         return sage.oo
>
> But:
> class NegativeInfinity(RationalConstant):
>     __metaclass__ = Singleton
>
> doesn't have an equivalent statement for _sage_ so I guess this bit is
> used: p = -1
>     q = 0
>
> I'll add a sage bit in there and see if it fixes the problem.
>

Yes, I just added

    def _sage_(self):
        import sage.all as sage

        return -(sage.oo)

in class NegativeInfinity and now the only part of that test that fails is
a trivial bit about ordering.

Francois

[Aaron Meurer]

OK. I will send in a patch to SymPy that fixes this upstream.

Aaron Meurer

[Aaron Meurer]

See https://github.com/sympy/sympy/pull/474.

Aaron Meurer

[Aaron Meurer]

Ondrej has given me PyPI access, so I've uploaded the stuff there.
You should now be able to pip install sympy and get 0.7.0

Aaron Meurer