Sage 3.1.2 Release Tour

Doctest Coverage Hits 60%

• Mike Hansen wrote doctests for almost all pexpect interfaces, which will ensure greater stability across the board.

Hidden Markov Models

Notebook Bugs

• Many bugs introduced in 3.1.1 were fixed by Mike Hansen and Timothy Clemans.
• A new testing procedure was implemented, hopefully preventing regressions like in 3.1.1 in the future.

New Structure for Partition Refinement

• Hypergraphs (i.e. incidence structures) -- this includes simplicial complexes and block designs

Improved Dense Linear Algebra over GF(2)

• M4RI (http://m4ri.sagemath.org) was updated to the newest upstream release which

  • provides much improved performance for multiplication,
  • provides improved performance for elimination,
  • contains several build and bugfixes.
• hashs and matrix pickling was much improved

• dense matrices over \mathbb{F}_2 can now be written to/read from 1-bit PNG images

New PolyBoRi Version (0.5) and Improved Interface

• PolyBoRi was upgraded from 0.3 to 0.5rc

• mq.SR now returns PolyBoRi equation systems if asked to

• support for boolean polynomial interpolation was added

QEPCAD Interface

Developer's Handbook

• John H Palmieri rewrote/rearranged large parts of the 'Programming Guide' (now 'Developer's Guide') which should make getting started easier for new developers.

Improved 64-bit OSX Support

Fast Numerical Integration

GAP Meataxe Interface

• In the module matrix_group, the method module_composition_factors interfaces with GAP's [http://www.gap-system.org/Manuals/doc/htm/ref/CHAP067.htm Meataxe] implementation. This will return decomposition information for a G-module, for any matrix group G over a finite field.

Better SymPy Integration

Faster Determinants of Matrices over Multivariate Polynomial Rings

Real Number Inputs Improved