SymPy 0.5.10 released

Changes:

• view renamed to preview, pngview, pdfview, dviview added (commit)
• latex printer was rewritten, preview uses builtin pyglet instead of pygame (commit 1, 2)
• square root denesting implemented (commit)
• parser of simple Mathematica expressions added (commit)
• TeXmacs interface written (commit)
• some integration fixes (commit 1, 2, 3)
• line width in 2D plotting can be specified (commit)
• README was updated (commit 1, 2)
• pyglet and mpmath were updated and moved to sympy/thirdparty (commit 1, 2, 3, 4, 5)
• all sys.path hacks were moved to just 2 places - pyglet and examples (commit 1, 2, 3)
• SymPy objects should work in numpy arrays now (commit 1, 2)
• hand written sympify() parser was rewritten and simplified using Python AST (commit)

See also Changes.

Google Highly Open Participation Contest 2007-8

SymPy participates in the Google Highly Open Participation Contest 2007-8, if you are a high school student, go for it. Last chance to claim a task is January 22!

SymPy 0.5.9 released

Changes:

* Differential solvers were polished
* isympy now predefines f as a function
* Matrix printing improved
* Printing internals were documented

See Changes for more info.

Blogs

We'll use this blog for official announcements only from now on. Personal opinions will be on people's blogs, all of which are synchronised at planet.sympy.org.

We have implemented some new cool features in the Mercurial repository, so a new release will soon come out.

If you are curious, you can always find what code has been committed here:

http://hg.sympy.org/sympy

SAGE Days 6 wrap-up

SD6 is over, here are my final notes about the conference:

http://ondrejcertik.blogspot.com/2007/11/sage-days-6.html

SAGE is an exciting project. On SD6 I managed with the help of other SAGE developers to make SymPy play more nicely (after my patches are accepted, you will be able to freely mix SymPy and SAGE expressions and it will work).

SAGE Days 6

I am at SAGE Days 6, you can watch the progress on my blog.

Unicode printing

One very cool feature of SymPy, that Kirill recently committed, is a unicode printing. Start isympy and see for yourself:

$ bin/isympy 
Python 2.4.4 console for SymPy 0.5.6-hg. These commands were executed:
>>> from __future__ import division
>>> from sympy import *
>>> x, y, z = symbols('xyz')
>>> k, m, n = symbols('kmn', integer=True)
>>> Basic.set_repr_level(2)     # 2D output
>>> pprint_try_use_unicode()    # try to setup unicode pprint


In [1]: sqrt((sqrt(x+1))+1)
Out[1]: 
   ⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽
  ╱       ⎽⎽⎽⎽⎽⎽⎽ 
╲╱  1 + ╲╱ 1 + x  

In [2]: th, ph = Symbol("theta"), Symbol("phi")

In [3]: Integral(sin(th)/cos(ph), (th,0,pi), (ph, 0, 2*pi))
Out[3]: 
2*π π             
 ⌠  ⌠             
 ⎮  ⎮ sin(θ)      
 ⎮  ⎮ ────── dθ dφ
 ⎮  ⎮ cos(φ)      
 ⌡  ⌡             
 0  0             

More examples can be found on the wiki page PrettyPrinting.

Fredrik also played with the idea of ascii plotting. I am a huge fan of a terminal, because this is very versatile - I can use it over ssh, I can copy & paste, save the results to a file etc. I can easily script it. And the most important - I just prefer to write my programs in vim and execute them as a simple script. Any GUI, even the best one (or in the browser), is not giving me such a power. So I like the idea of making the terminal experience as pleasant as possible.