Coon's patch defines a patch from 4 curves forming a chain. 4-examples to Coon's patch are given following worksheet. Boundary curves in the examples are constructed by parametric cubic curves (in Bezier and Hermite form). First example is in 3D and comparable to parametric bicubic surface. Rest of examples are in 2D (abstract surface) which can be described shortly as:

• 2D Example#1: 4 circular-arc like curves are combined by Coon's patch to form a circular-like region

This post gives equation of stability region of a Runge-Kutta ODE solver (Dormand-Prince45) as implicit domain equation and ODE-IVP.

Contents are:

• Runge-Kutta solver is implemented
• Solver is applied to test equation and growth factor is obtained
• Stability regions are defined by separating hyperplane (GF=growth factor=1)
• Stability regions are plotted by bruteforce approach (implicitplot)
• Boundary of stability regions...