This function computes the value for C for each time and pool.
This function takes a Model object, which represents a system of ODEs of the form
dC(t)/dt = I(t) + A(t)C(t)
and solves the system for C(t). The numerical solver used can be specified in the constructor of the Model class
A matrix with m columns representing the number of pools, and n rows representing the times as specified by the argument
GeneralModel or another model creating function.
Carlos A. Sierra, Markus Mueller