An approach to verifying and debugging simulation models governed by ordinary differential equations: Part 1. Methodology for residual generation

• Published in: International journal for numerical methods in engineering 2003-06, Vol.57 (5), p.685-706
• Main Authors: Yuan, Zhiguo, Graham, Malcolm L., Lennox, James A.
• Format: Article
• Language: English
• Subjects: Computer programs; Computer simulation; Debugging; Differential equations; Error detection; Mathematical models; Methodology; model quality assurance; model verification; multi-version programming; ODE; Permissible error; simulation testing
• ISSN: 0029-5981; 1097-0207
• DOI: 10.1002/nme.698

For dynamic simulations to be credible, verification of the computer code must be an integral part of the modelling process. This two‐part paper describes a novel approach to verification through program testing and debugging. In Part 1, a methodology is presented for detecting and isolating coding errors using back‐to‐back testing. Residuals are generated by comparing the output of two independent implementations, in response to identical inputs. The key feature of the methodology is that a specially modified observer is created using one of the implementations, so as to impose an error‐dependent structure on these residuals. Each error can be associated with a fixed and known subspace, permitting errors to be isolated to specific equations in the code. It is shown that the geometric properties extend to multiple errors in either one of the two implementations. Copyright © 2003 John Wiley & Sons, Ltd.