**An improved incomplete Cholesky factorization**

Mark T. Jones, Paul E. Plassmann

Pages: 5-17

DOI: 10.1145/200979.200981

Incomplete factorization has been shown to be a good preconditioner for the conjugate gradient method on a wide variety of problems. It is well known that allowing some fill-in during the incomplete factorization can significantly reduce the...

**Algorithm 740: Fortran subroutines to compute improved incomplete Cholesky factorizations**

Mark T. Jones, Paul E. Plassmann

Pages: 18-19

DOI: 10.1145/200979.200986

Efficient and reliable code to compute incomplete Cholesky factors of sparse matrices for use as preconditioners in a conjugate gradient algorithm is described. This code implements two recently developed, improved incomplete factorization...

**Algorithm 741: least-squares solution of a linear, bordered, block-diagonal system of equations**

Richard D. Ray

Pages: 20-25

DOI: 10.1145/200979.200987

A package of Fortran subroutines is presented for the least-squares solution of a system of overdetermined, full-rank, linear equations with single-bordered block-diagonal structure. This structure allows for a natural sequential processing, one...

**Fast floating-point processing in Common Lisp**

Richard J. Fateman, Kevin A. Broughan, Diane K. Willcock, Duane Rettig

Pages: 26-62

DOI: 10.1145/200979.200989

Lisp, one of the oldest higher-level programming languages, has rarely been used for fast numerical (floating-point) computation. We explore the benefits of Common Lisp, an emerging new language standard with some excellent implementations, for...

**A Fortran 90 environment for research and prototyping of enclosure algorithms for nonlinear equations and global optimization**

R. Baker Kearfott

Pages: 63-78

DOI: 10.1145/200979.200991

An environment for general research into and prototyping of algorithms for reliable constrained and unconstrained global nonlinear optimization and reliable enclosure of all roots of nonlinear systems of equations, with or without inequality...

**Software distribution using Xnetlib**

Jack Dongarra, Tom Rowan, Reed Wade

Pages: 79-88

DOI: 10.1145/200979.200995

Xnetlib is a new tool for software distribution. Whereas its predecessor netlib uses email as the user interface to its large collection of public-domain mathematical software, Xnetlib uses an X Window interface and socket-based communication....

**Repository mirroring**

Eric Grosse

Pages: 89-97

DOI: 10.1145/200979.201000

Distributed administration of network repositories demands a low-overhead procedure for cooperating repositories around the world to ensure they hold identical contents. Netlib has adopted some refinements on the widespread scheme of anonymous...

**Algorithm 742: L2CXFT**: a Fortran subroutine for least-squares data fitting with nonnegative second divided differences

I. C. Demetriou

Pages: 98-110

DOI: 10.1145/200979.201039

A Fortran subroutine applies the method of Demetriou and Powell [1991] to restore convexity in n measurements of a convex function contaminated by random errors. The method minimizes the sum of the squares of the errors, subject to nonnegativity...

**The accelerated integer GCD algorithm**

Kenneth Weber

Pages: 111-122

DOI: 10.1145/200979.201042

Since the greatest common divisor (GCD) of two integers is a basic arithmetic operation used in many mathematical software systems, new algorithms for its computation are of widespread interest. The accelerated integer GCD algorithm discussed...

**CUTE**: constrained and unconstrained testing environment

I. Bongartz, A. R. Conn, Nick Gould, Ph. L. Toint

Pages: 123-160

DOI: 10.1145/200979.201043

The purpose of this article is to discuss the scope and functionality of a versatile environment for testing small- and large-scale nonlinear optimization algorithms. Although many of these facilities were originally produced by the authors in...