Modelling the dynamics of tumor and immune cells via 3 sets of time-delayed differential equations. While time-delayed differential equations are notoriously difficult to solve, they can be approximated with difference equations which can be numerically solved/ simulated.

The work is based on the following paper.

Kartal, S.. “Mathematical modeling and analysis of tumor-immune system interaction by using Lotka-Volterra predator-prey like model with piecewise constant arguments.” Periodicals of Engineering and Natural Sciences (PEN) 2 (2014): n. pag.