Compute and return the derivatives for a model of class \(\cal X\) - the dynamics of infection and immunity in humans or other vertebrate host.
The function dispatches on class(Xpar).
Value
the derivatives as a numeric vector
Compute and return the derivatives for a model of class \(\cal X\) - the dynamics of infection and immunity in humans or other vertebrate host.
The function dispatches on class(Xpar).
the derivatives as a numeric vector