April 27, 2004
   FOR IMMEDIATE RELEASE

Visual Numerics Announces Immediate Availability of the IMSL® Thread Safe Fortran Numerical Library

Featuring 100% Thread Safety for Speed and Reliability in High Performance Computing Environments

SAN RAMON, Calif., April 27, 2004 -- Visual Numerics Inc., a leading provider of numerical analysis and visualization software, today announced the immediate availability of the IMSL Thread Safe Fortran Numerical Library. This latest addition to the Company's flagship IMSL product for Fortran developers has added complete thread safety for improved speed and performance in high performance computing environments. With unmatched thread safe functionality and Visual Numerics' historical superiority in accuracy and reliability, the IMSL Thread Safe Fortran Numerical Library is the most powerful collection of mathematical and statistical algorithms available. It is ideal for application development in high performance computing organizations, such as government laboratories and university research centers, where speed and accuracy are critical.

The IMSL Thread Safe Fortran Numerical Library is the only commercially available library that has 100% thread safety, meaning that the routines have been checked and tested to ensure that multi-threaded applications can rely on the entire library 100% of the time. Complete thread safety allows programmers to call the same routine multiple times in the program and have multiple instances of the routine running on multiple threads, improving performance and simplifying programming.

"Speed is imperative in high performance computing environments, and Visual Numerics' IMSL Fortran Numerical Library is one of the fastest, most reliable, and extensive sets of algorithms we have found," said Dr. David Halpern, Associate Professor, Department of Mathematics, University of Alabama. "Visual Numerics' latest Fortran offering sets a new standard."

"While other offerings on the market have high numbers of thread-unsafe algorithms in their libraries, our ongoing goal is to offer developers the most accurate and trustworthy Fortran algorithms available, " said Phil Fraher, COO of Visual Numerics. "Our new IMSL Thread Safe Fortran Numerical Library leverages proven technology and provides users with even greater ease of use, and speed."

Because of the strong background Fortran has in high performance computing, it appeals to highly performance-driven numerical computation developers. The IMSL Thread Safe Fortran Numerical Library is currently available on the following platforms:

• Sun Solaris (32-bit)
• Sun Solaris (64-bit)
• IBM AIX (64 bit)

The latest release of the IMSL Thread Safe Fortran Numerical Library expands Visual Numerics' 30-year-trusted IMSL libraries, which have become the most widely used mathematical and statistical libraries for developing data analysis applications. The IMSL product family includes libraries of high-end math and statistical codes that developers can embed directly into their Fortran, C, or Java code, thereby accelerating development, improving quality, and reducing development cost. As is true for all previous versions of the IMSL Libraries, the IMSL Thread Safe Fortran Numerical Library is also fully backward compatible and ensures that legacy code can run on future releases.

About Visual Numerics, Inc.:
Visual Numerics (www.vni.com) has provided technical software solutions for numerical analysis and visualization for over three decades. The company's software products help users understand complex data from a variety of sources and build business-critical applications. Visual Numerics offers two product lines: the IMSL Numerical Libraries for powerful mathematical and statistical analysis and the PV-WAVE visual data analysis development environment. Visual Numerics also offers consulting services for applications that involve mathematical, statistical, or visual analysis. Major corporations, academic institutions, and research laboratories worldwide use Visual Numerics' software tools, including such high profile companies as: Bear, Stearns & Company; Deutsche Bank; Sandia National Laboratories; Boeing Company; Dow Chemical and Coleman Research Corp. This large and diverse customer base is supported through a direct sales force, wholly owned international subsidiaries, and international distributors. For more information about Visual Numerics, please visit www.vni.com.

Editor's Notes:
Visual Numerics and PV-WAVE are registered trademarks of Visual Numerics, Inc. in the US and other countries. IMSL, JMSL, JWAVE, TS-WAVE and Knowledge in Motion are trademarks of Visual Numerics, Inc. All other company, product or brand names are the property of their respective owners.