SIR: The SIR epidemic model
In mjg211/phaseR: Phase Plane Analysis of One- And Two-Dimensional Autonomous ODE Systems

SIR	R Documentation

The SIR epidemic model

The derivative function of the SIR epidemic model, an example of a two-dimensional autonomous ODE system.

SIR(t, y, parameters)

`t`	The value of t, the independent variable, to evaluate the derivative at. Should be a `numeric` `vector` of `length` one.
`y`	The values of x and y, the dependent variables, to evaluate the derivative at. Should be a `numeric` `vector` of `length` two.
`parameters`	The values of the parameters of the system. Should be a `numeric` `vector` with parameters specified in the following order: β, ν.

SIR evaluates the derivative of the following ODE at the point (t, x, y):

dx/dt = -βxy, dy/dt = βxy - νy.

Its format is designed to be compatible with ode from the deSolve package.

Returns a list containing the values of the two derivatives at (t, x, y).

Michael J Grayling