Lastly, is a 20 session Stanford video course - http://academicearth.org/courses/introduction-to-linear-dynamical-systems I will continue to look for more applicable stuff. Ron Marks" Steven Winegarden notes that SPICE , a widely used electronics simulation program uses large simultaneous equations extensively to do its modeling. http://new.eetimes.com/design/automotive-design/4009934/Understand-basics-of-SPICE-environment-for-circuit-analysis-and-design-Part-1-of-2 contains the following: ABC-SPICE-Matrix.pdf . The following URLs