As a contribution to Free Software [1] and to the Linux community, we offer the complete OPEN DESIRE modeling/simulation package for Linux, including PC binaries, source code in c, a comprehensive manual, and over 200 program examples without any charge except for media, handling, and shiping, under the GNU General Public Licence [1] proposed by the Free Software Foundation. We will burn you a CD if you send us $15 for media, handling and shipping; contact gatmkorn@aol.com.

OPEN DESIRE is written entirely in portable c and is roughly one-half as fast as the Windows version, which uses assembly language. Otherwise, OPEN DESIRE, has the full functionality of DESIRE/2000. Itt employs Linux editor windows (gedit) instead of the special DESIRE Editor Window, which is written in c++, and Xwindows graphics.

OPEN DESIRE includes an experiment-protocol script interpreter and a runtime-compiled industrial-strength differential-equation solver. We can solve up to 40,000 first-order differential equations with fixed- and variable-step Runge-Kutta integration, or up to 600 differential equations with variable-step/variable-order rules for stiff systems, all in double-precision floating-point format. A powerful vectorizing compiler built into DESIRE permits model replication for vectorized Monte Carlo studies. Differential-equation and difference-equation models use an easily readable mathematical notation and can mix scalar and vector equations. The model code compiles and executes immediately on a typed or programmed drun command to produce solution displays or listings for truly interactive modeling.

Such "direct-executing" simulation runs can be initialized and run by typed interactive commands. More often, though, an interpreted experiment-protocol script calls repeated simulation runs (say for parameter-influence or optimization studies) and manipulates parameters and initial conditions. Experiment-protocol scripts resemble advanced Basic programs and can, in fact, be used for general-purpose mathematics. They handle vectors and matrices, and also complex numbers for complex frequency-response and root-locus plots. Scripts can also invoke operating-system functions and external programs. DESIRE experiment-protocol scripts can access operating-system commands and external programs as well as DESIRE operations.

Model equations and experiment-protocol scripts are entered in editor windows. You can select and run programs from multiple Editor Windows to compare models or protocols. Programs can generate special editor windows used as dialog boxes.

DESIRE programming, including simulation of neural networks and fuzzy logic, is described on our Web site (http://members.aol.com/gatmkorn). Two textbooks [2,3] describe earlier versions of DESIRE, and Refs. 4-6 discuss recent applications of the new vector compiler. We have run OPEN DESIRE on personal computers under different Linux releases using either GNOME or KDE windows. The included c source code should compile with minimal modifications for other Linux systems, and also many Unix systems with Xwindows graphics; we have successfully tried SOLARIS and CYGWIN (Unix under Windows).

We contribute the new OPEN DESIRE modeling/simulation package for Linux, including source code and manual, as Free Software, under a GNU General Public License .[1]

There will never be any charge except for media, handling, and postage; contact gatmkorn@aol.com.

As specified in the Free Software Association’s Web page,[1] their use of the word "free" does not refer to such no-charge distribution (anyone can, in fact, redistribute the program with support or other added features, for a fee). "Free" rather refers to the opportunity to use, change, and distribute the source code with complete freedom. The GNU General Public License was carefully written to force all redistributions to include source code, and to keep Bad Guys from restricting part of the code with software patents. The license also avoids any and all warranties. "Open" software, as opposed to "free" software, additionally permits various tie-ins with commercial projects, which is sometimes useful.[1]

Again, the purpose of the General Public License is not cost-free distribution, but free, widespread development of new software, with truly free-market competition between more and more improved programs. With continued development, small and large businesses can, of course, benefit handsomely from inexpensive software like Linux and Open Office.[2]

Above all, we believe very strongly that academic computer-science and computer-engineering departments ought to support and promote free-software projects whenever they can. Academic departments have useful manpower and resources, and academic software research, part of the teaching/learning process, is relatively inexpensive. Inspiring source code – think of the excellent GNU compilers, the Linux kernel, free Internet programs, Octave (similar to Matlab) – is freely available and readily used in courses on software principles, software development, and software project management. Student projects can access true hands-on knowhow with good source code. The Free Software community includes top programmers all over the world, and students are sure to benefit from such contacts. Quite beyond elegant programming, we believe that your students must learn, from your example, a measure of dedication to freely expanding scientific and professional knowledge.

Granino A. and Theresa M. Korn

G. A. and T.M. Korn Industrial Consultants

Chelan, WA November 1, 2005

1, Free Software Foundation, Inc.

59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

http://www.gnu.org/home.html

2. http://www.openoffice.org