Computer Methods for Ordinary Differential Equations and Differential-Algebraic Equations

In this chapter and the next two we will consider an ordinary differential equation (ODE) system with m components,
subject to m two-point boundary conditions
We denote the Jacobian matrices of g( u, v) with respect to its first and second argument vectors by
Often in applications, g is linear; i.e., the boundary conditions can be written as
for some given data b, [25] and the m m matrices B 0 and B b are constant.
Also, often in applications the boundary conditions are separated; i.e., each of the components of g is given either at t = 0 or at t = b, but none involves both ends simultaneously. [26] In this case for each i, 1 ? i ? m, either the ith row of B 0 or the ith row of B b are identically zero.
Recall Example 1.4 (the vibrating spring),

where p( t) > 0, q( t) ? 0 for all 0 ? t ? b. In more independent variables, a problem like this corresponds to an elliptic partial differential equation.
To convert this into a system we have two popular options.
The standard option is to set