# Wiki

# m4ri / M4RI-20130416

# Release Notes

M4RI-20130416 was released on 22 March 2013. It is available at:

http://m4ri.sagemath.org/downloads/

## About M4RI

M4RI is a library for fast arithmetic with dense matrices over F2. The name M4RI comes from the first implemented algorithm: The "Method of the Four Russians" inversion algorithm published by Gregory Bard. This algorithm in turn is named after the "Method of the Four Russians" multiplication algorithm which is probably better referred to as Kronrod's method. M4RI implements asymptotically fast matrix multiplication, linear system solving, reduced row echelon forms, PLE decomposition and basic arithmetic. M4RI is used by the Sage mathematics software and the PolyBoRi library. M4RI is available under the General Public License Version 2 or later (GPLv2+).

## Changes

- adding mzp_copy() for convenience
- performance improvements for small matrices (say, 64 x 64)
- dropped requiring of autoconf 2.64 (we don't need it)

## Supported Platforms

**make check** passes on the following platforms

- x86_64 Linux (sage.math.washington, redhawk.math.washington);
- x86 OSX (bsd.math.washington);
- ia64 Linux (iras.skynet);
- x86 Linux (Pentium 4, cicero.skynet);

The code does not currently build under Windows, help in this area is appreciated.

Updated