SuperLU is a general purpose library for the direct solution of
large, sparse, nonsymmetric systems of linear equations on high
performance machines. The library is written in C and is callable
from either C or Fortran. The library routines will perform an LU
decomposition with partial pivoting and triangular system solves
through forward and back substitution. The LU factorization routines
can handle non-square matrices but the triangular solves are
performed only for square matrices. The matrix columns may be
preordered (before factorization) either through library or user
supplied routines. This preordering for sparsity is completely
separate from the factorization. Working precision iterative
refinement subroutines are provided for improved backward
stability. Routines are also provided to equilibrate the system,
estimate the condition number, calculate the relative backward
error, and estimate error bounds for the refined solutions.
This is the multi-threaded version (POSIX threads or OpenMP).