The LINPACK library, for linear equations and linear least squares problems, linear systems whose matrices are general, banded, symmetric indefinite, symmetric positive definite, triangular, and tridiagonal square. In addition, the package computes the QR and singular value decompositions of rectangular matrices and applies them to least squares problems.
Many programs now use newer mathematical libraries such as LAPACK, or Intel MKL. LINPACK retains use as a benchmarking standard.
For information on LINPACK, see the complib or sgimath man pages (man complib or man sgimath)