- april - A subset of APL (A Programming Language) compiling to Common Lisp
- GSLL - GNU Scientific Library for Lisp allows you to use the GNU Scientific Library (GSL) from Common Lisp
- lisp-matrix - A matrix linear algebra library for common lisp building on work by Mark Hoemmen, Evan Monroig, Tamas Papp and Rif
- MatLisp - A BLAS and LAPACK linear algebra library wrapper which makes their features accessible through a set of CLOS classes
- NLISP - NLISP is an environment for numerical computation and visualisation like IDL or Matlab

matrix

Packages for matrix algebra. AJ Rossini wrote a nice summary about some of these packages.