JAMA is a
software library
In computing, a library is a collection of resources that can be leveraged during software development to implement a computer program. Commonly, a library consists of executable code such as compiled functions and classes, or a library can ...
for performing
numerical linear algebra
Numerical linear algebra, sometimes called applied linear algebra, is the study of how matrix operations can be used to create computer algorithms which efficiently and accurately provide approximate answers to questions in continuous mathemati ...
tasks created at
National Institute of Standards and Technology
The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into Outline of p ...
in 1998 similar in functionality to
LAPACK
LAPACK ("Linear Algebra Package") is a standard software library for numerical linear algebra. It provides routines for solving systems of linear equations and linear least squares, eigenvalue problems, and singular value decomposition. It als ...
.
Functionality
The main capabilities provided by JAMA are:
*
Eigensystem
In linear algebra, an eigenvector ( ) or characteristic vector is a vector that has its direction unchanged (or reversed) by a given linear transformation. More precisely, an eigenvector \mathbf v of a linear transformation T is scaled by a c ...
solving
*
LU decomposition
In numerical analysis and linear algebra, lower–upper (LU) decomposition or factorization factors a matrix as the product of a lower triangular matrix and an upper triangular matrix (see matrix multiplication and matrix decomposition). The produ ...
*
Singular value decomposition
In linear algebra, the singular value decomposition (SVD) is a Matrix decomposition, factorization of a real number, real or complex number, complex matrix (mathematics), matrix into a rotation, followed by a rescaling followed by another rota ...
*
QR decomposition
In linear algebra, a QR decomposition, also known as a QR factorization or QU factorization, is a decomposition of a matrix ''A'' into a product ''A'' = ''QR'' of an orthonormal matrix ''Q'' and an upper triangular matrix ''R''. QR decom ...
*
Cholesky decomposition
In linear algebra, the Cholesky decomposition or Cholesky factorization (pronounced ) is a decomposition of a Hermitian, positive-definite matrix into the product of a lower triangular matrix and its conjugate transpose, which is useful for eff ...
Versions exist for both
C++ and the
Java programming language
Java is a high-level, general-purpose, memory-safe, object-oriented programming language. It is intended to let programmers ''write once, run anywhere'' ( WORA), meaning that compiled Java code can run on all platforms that support Jav ...
. The C++ version uses the
Template Numerical Toolkit for lower-level operations. The Java version provides the lower-level operations itself.
History
As work of US governmental organization the algorithm and
source code
In computing, source code, or simply code or source, is a plain text computer program written in a programming language. A programmer writes the human readable source code to control the behavior of a computer.
Since a computer, at base, only ...
have been released to the
public domain
The public domain (PD) consists of all the creative work to which no Exclusive exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly Waiver, waived, or may be inapplicable. Because no one holds ...
around 1998.
JAMA : A Java Matrix Package
on math.nist.gov JAMA has had little development since the year 2000,
Usage Example
Example of Singular Value Decomposition (SVD):
SingularValueDecomposition s = matA.svd();
Matrix U = s.getU();
Matrix S = s.getS();
Matrix V = s.getV();
Example of matrix multiplication:
Matrix result = A.times(B);
See also
* List of numerical libraries
This is a list of numerical libraries, which are libraries used in software development for performing numerical calculations. It is not a complete listing but is instead a list of numerical libraries with articles on Wikipedia, with few exceptio ...
References
{{reflist, 30em, refs=
[{{cite web , url=http://math.nist.gov/javanumerics/jama/ChangeLog , title=JAMA Change Log , date=November 8, 2012 , work=JAMA, publisher=NIST, accessdate=November 30, 2012]
[{{cite web , url=http://math.nist.gov/javanumerics/jama/ , title=JAMA Project Page , work=JAMA, publisher=NIST, accessdate=November 30, 2012]
External links
JAMA/C++ download and documentation page
at NIST
JAMA/Java homepage
at NIST
Numerical software
Public-domain software with source code
C++ numerical libraries