NMatrix
Description
NMatrix is an experimental linear algebra library for Ruby, written mostly in C and C++. It can be used with or without SciRuby, but is part of the SciRuby project.
NMatrix was inspired by and based heavily upon NArray, by Masahiro Tanaka.
WARNING:
Please be aware that SciRuby and NMatrix are ALPHA status. If you're thinking of using SciRuby/NMatrix to write missioncritical code, such as for driving a car or flying a space shuttle, you may wish to choose other software (for now).
You should also be aware that NMatrix and NArray are incompatible with one another; you should not try to require both at the same time. Unfortunately, that causes problems with Ruby/GSL, which currently depends upon NArray. As such, we are working on a patch for Ruby/GSL.
Features
The following features exist in the current version of NMatrix (0.0.2):

Matrix storage containers: dense, yale, list (more to come)

Data types: uint8, int8, int16, int32, int64, float32, float64, complex64, complex128, rational64, rational128 (incomplete)

Conversion between storage and data types (except fromcomplex, and fromfloattorational)

Elementwise operations and comparisons for dense and yale

Matrixmatrix multiplication for dense (using ATLAS) and yale

Matrixvector multiplication for dense (using ATLAS)

Dense and list matrix slicing and referencing

Matlab .MAT v5 file input

C and C++ API

BLAS internal implementations (no library) and ATLAS (with library) access:

Level 1: xROT, xROTG (BLAS dtypes only)

Level 2: xGEMV

Level 3: xGEMM, xTRSM


LAPACK ATLAS access:

xGETRF, xGETRI, xGETRS, xGESV (Gaussian elimination)

xPOTRF, xPOTRI, xPOTRS, xPOSV (Cholesky factorization)

xLASWP, xSCAL, xLAUUM


LAPACKless internal implementations (no LAPACK needed and working on nonBLAS dtypes):

xGETRF

xLASWP, xSCAL

xLAUUM (no LAPACK needed, but BLAS dtypes only)


LU decomposition

Matrix inversions (requires LAPACK; BLAS dtypes only)

Determinant calculation for BLAS dtypes
Planned Features (ShorttoMedium Term)
These are features planned for NMatrix 0.1.0, our first beta.

calculation of determinant (LAPACKfree), trace, and eigenvalues (characteristic polynomial) (0.1.0)

exponentials and square roots

matrix inversions (LAPACKfree)

matrix decomposition/factorization

calculation of norms

tensor products

principal component analysis (PCA)

improved file I/O

operation scheduling

parallelization of some types of operations

optimization of nonBLAS data types on BLASlike operations (e.g., matrix multiplication for rational numbers)

Ruby/GSL interoperability
SYNOPSIS:
For full instructions, please see sciruby.com/nmatrix. Generally, you should be able to do
gem install nmatrix
However, you will need to install ATLAS with CBLAS first. Those directions can be found at our website.
NOTE: The above command will not give you 0.0.2, which is not yet complete. To obtain 0.0.2, you should use the following sequence of commands:
git clone https://github.com/SciRuby/nmatrix.git
cd nmatrix/
rake compile
rake repackage
gem install pkg/nmatrix0.0.2.gem
If you get errors about clapack.h or cblas.h, figure out where your ATLAS headers are using:
locate clapack.h
If you're a Mac user, we recommend you search for cblas.h instead.
Then, tell your system:
export C_INCLUDE_PATH=/usr/local/atlas/include
export CPLUS_INCLUDE_PATH=/usr/local/atlas/include
Finally, try compiling again.
REQUIREMENTS:

ATLAS and LAPACK, probably

GCC 4.3

Ruby 1.9

packable 1.3.5 (used for I/O)
INSTALLATION:
See Synopsis (above) for now. Gem coming later.
More detailed installation instructions are available at here
DEVELOPERS:
Code in the master branch of SciRuby/nmatrix on github should compile and link, but is not necessarily stable. You might also check out the dev branch if master hasn't been updated in some time.
git clone https://github.com/mohawkjohn/nmatrix.git
Before commiting any code, you MUST read our Contributor Agreement.
LICENSE:
Copyright © 2012, The Ruby Science Foundation.
All rights reserved.
NMatrix, along with SciRuby, is licensed under the BSD 2clause license. See LICENSE.txt for details.
DONATIONS:
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