JAMA is a basic linear algebra package for Java and provides classes for creating and manipulating real, dense matrices. JAMA consists of six Java classes Matrix, CholeskyDecomposition, LUDecomposition, QRDecomposition, SingularValueDecomposition and EigenvalueDecomposition. JAMA is being developed as and is intended to be the standard matrix package for Java and will be presented to Java Grande and Sun as such. A Numerical Library . From Visual Numerics, the folks that brought you IMSL, comes JNL, a Java numerical library.
All classes use double precision floating point as the underlying float type.
If you are extremely interested in numerical computation in Java, you may be interested in attending the ACM Java Grande Conference in June. For more information, visit the official web site . Nikola Vojtov was kind enough to share his list of bookmarks of applications of Java in the sciences. Most of the links deal with biological applications however, there are some that deal with applications in physics and mathematics. You can check out the full list of links on Nikola's web site .