The algorithms discussed and applied in this chapter will appear as if they are for the single, first order, ordinary differential equation. Actually they are more general in that
should be considered a vector equation with
and 
N-dimensional vectors (in the computing sense
of arrays of numbers):
In a more explicit form, the differential equations we solve must have the form:
Changing the techniques so that they take array as argumnets instead of numbers allows us to solve any equation which can be represented in this form.