** **

**1. NAME AND TITLE**

SAHYB-2**: **Solution of Ordinary Differential
Equation with User-Supplied Subroutine.

**2. CONTRIBUTOR**

Commission
des Communautes Europeennes, CETIS, 21020 – Ispra, Italy through the OECD
Nuclear Energy Agency Data Bank, Issy-les-Moulineaux, France.

**3. CODING LANGUAGE
AND COMPUTER**

Fortran IV; IBM 360 Series (C00820I036000).

**4. NATURE OF
PROBLEM SOLVED**

SAHYB-2 is a general purpose program for the solution of ordinary differential equations. These are written in a user-supplied subroutine called DER, which uses notations very close to mathematical formulas. Special mathematical functions included in the program are function generation, delay generation, steps, ramps and pulses, as well as a simplified standard output procedure - boundary value problems or parametric optimization may be handled by iterations adding a subroutine called REPEAT.

**5. METHOD OF
SOLUTION**

Integration is carried out by constant step fourth-order Runge-Kutta method, or by a fixed or variable step Adams-Moulton predictor corrector method.

**6. RESTRICTIONS OR
LIMITATIONS**

Maximum 150 differential equations of the first order;

Maximum 30 tables for function generator or delay lines.

**7. TYPICAL RUNNING
TIME**

Varies greatly with the size of problem - range from few minutes for small systems (less than 10 differential equations) to a half hour for large problems.

**8. COMPUTER
HARDWARE REQUIREMENTS**

IBM 360.

**9. COMPUTER
SOFTWARE REQUIREMENTS**

IBM 360 OS (Standard FORTRAN monitor.).

**10. REFERENCES**

**a) Included Documentation**

** **None listed.

**b) Background Documentation**

H. D Hoop and R. Monterosso, “SAHYB-2 - A Programme for the Solution of Differential Equations Using an Analogue-Oriented Language,” Report EURATOM 3622/E.

**11. CONTENTS OF CODE
PACKAGE**

The package is distributed on a CD with a compressed zip file including source files, and sample data and output.

**12. DATE OF ABSTRACT**

December 2013.

**KEYWORDS**: ORDINARY
DIFFERENTIAL EQUATIONS, PROGRAMMING LANGUAGES, SPECIAL FUNCTIONS