1.1) What is this FAQ for?
To provide basic introductory information and answers to frequently asked questions about Netlib.
1.2) Where can I get a copy of this FAQ?
The most recent version of this FAQ can be retrieved from
1.3) Where should I send comments and corrections for this FAQ?
Send email to email@example.com
1.4) What is the Netlib Question and Answer Forum? Netlib Question and Answer Forum is bulletin board moderated by Netlib group. Feel free to post, answer, and discuss questions of other people.
2.1) What is Netlib?
The Netlib repository contains freely available software, documents, and databases of interest to the numerical, scientific computing, and other communities. The repository is maintained by AT&T Bell Laboratories, the University of Tennessee and Oak Ridge National Laboratory, and by colleagues world-wide. The collection is replicated at several sites around the world, automatically synchronized, to provide reliable and network efficient service to the global community.
2.2) How do I retrieve software or documents from Netlib?
Mechanisms include the World Wide Web (WWW), email, ftp, gopher, xnetlib:
send indexto firstname.lastname@example.org to receive a contents summary and instructions.
2.3) Are there restrictions on the use of software
retrieved from Netlib?
Most netlib software packages have no restrictions on their use but we recommend you check with the authors to be sure. Checking with the authors is a nice courtesy anyway since many authors like to know how their codes are being used.
2.4) How do I submit software or documents to Netlib?
Direct inquiries to email@example.com
2.5) Where are the official Netlib mirror sites?
2.6) Which sites use the Netlib email server to distribute other
types of software?
A collection of statistical software is available from
2.7) Where can I find more information about Netlib?
A collection of working notes related to the Netlib repository is available at :
2.8) What is Xnetlib?
Xnetlib is an X Window System application that provides interactive file access and database query processing from multiple servers through TCP/IP connections. Xnetlib currently provides access to the Netlib software and document repository, and the NA-NET Whitepages Database.
The last release of Xnetlib was version 1.3. Since its release, most of its capabilities have been superceded by World Wide Web browsers like Mosiac or Netscape. Since most of the efforts at Netlib are presently geared more towards the World Wide Web, we recommend using a WWW browser.
2.9) How do I find a particular routine?
The most powerful search capabilities in Netlib are provided through the interface at
The Netlib email interface has a similar capability. Send the email message "find foo" to firstname.lastname@example.org or another Netlib site.
2.10) How do I find software to solve a particular problem?
One way is to identify appropriate keywords and then use the Web search interface at
The GAMS mathematical software classification system enables users to find suitable software by browsing the problem hierarchy. You can use GAMS from the search interface or by linking to
Another way is to browse the Netlib libraries list and to identify libraries appropriate to your problem. You can then browse the contents of these individual libraries. Using a Web interface, look at
2.11) I can't get a program to work. What should I do?
Technical questions about the proper use of a software package should be directed to the authors of that package.
2.12) Where can I find documentation for a particular program?
Documentation for a particular software package generally comes with the software bundle or resides in the same directory as the software. Note that much of the software in Netlib is self-documenting - the comments in the code provide all the documentation you need.
2.13) What is dependency checking and how does it work?
Dependency checking is Netlib's mechanism for sending routines called by those routines a user has explicitly selected. A single request for the highest level routine should therefore get all the routines a user needs.
Dependencies are generated from a script that looks at the load map for each software package. A manually edited file tells Netlib which directories to scan for dependent routines.
2.14) I requested some software but didn't get all the routines
I needed. Why?
Send email to email@example.com describing the behavior.
2.15) What and where are the BLAS?
The BLAS (Basic Linear Algebra Subprograms) are high quality "building block" routines for performing basic vector and matrix operations. Level 1 BLAS do vector-vector operations, Level 2 BLAS do matrix-vector operations, and Level 3 BLAS do matrix-matrix operations. Because the BLAS are efficient, portable, and widely available, they're commonly used in the development of high quality linear algebra software, LINPACK and LAPACK for example.
The BLAS are located in the blas directory of Netlib.
2.16) Why don't I get needed BLAS automatically when I select
LAPACK is designed especially for high-performance computing so the LAPACK group prefers that users use tuned vendor-supplied BLAS whenever possible.
2.17) What and where are
These routines are used to specify machine-dependent parameters such as your machine's precision. They're used by several packages, most commonly to ensure that tolerances used in the software is reasonable for a particular machine.
The easiest to use versions of the routines r1mach, d1mach, and i1mach are located in the blas directory of Netlib. These versions of r1mach and d1mach attempt to determine machine characteristics automatically.
The original versions of r1mach, d1mach, and i1mach, in the slatec/src directory, require a user to scan their source and to uncomment the statements specifying the constants for his particular machine. Constants for some architectures are not explicitly identified in the comments of r1mach, d1mach, and i1mach. For those architectures conforming to the IEEE floating-point standard, and most newer ones do, you can locate and uncomment the IEEE-conforming constants in the routines.
2.18) How can I unpack foo.tar.z?
mv foo.tar.z foo.tar.Z uncompress foo.tar.Z tar xvf foo.tar
2.19) How can I unpack foo.tgz?
gunzip foo.tgz tar xvf foo.tarFor Windows and Mac, commercial tools are available from www.winzip.com and www.stuffit.com.
2.20) Does Netlib offer technical support?
No. Technical questions should be directed to the authors of the software package.
2.21) Can I download all/lots of the Netlib repository?
Yes. Note however that downloading software that isn't going to be used right away tends to waste time and space. When you're finally ready to use it you may end up downloading it again from Netlib just be sure you have the latest version. For this same reason, downloading all of Netlib's software and storing it someplace is not the best way to build a local software repository.
2.22) How can I become a Netlib mirror site?
First check the list of mirror sites (Question 2.5) to see if an existing Netlib site could meet your needs. Then read the policy on becoming a Netlib mirror site at
2.23) How can I use the Netlib program to run my own repository?
You can retrieve the source code for the Netlib email system from the "netlib" directory of the Netlib repository. For example, to retrieve the Netlib program by email send the message
send netlib from netlibto firstname.lastname@example.org.
2.24) What if I have other questions about Netlib?
The srwn directory contains papers that may be of assistance. Point your Web browser to