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8 Lotka-Volterra system with delays

The system of two differential equations with delays

$\displaystyle \left\{\vphantom{
\begin{array}{l}
\vspace{2mm} \displaystyle
\do...
...-\tau}^{0} F_2(s)   x_1 (t+s)   ds
\biggr]   x_2 (t)   ,\end{array}}\right.$$\displaystyle \begin{array}{l}
\vspace{2mm} \displaystyle
\dot x_1 (t)   =   ...
...limits_{-\tau}^{0} F_2(s)   x_1 (t+s)   ds
\biggr]   x_2 (t)   ,\end{array}$ (8.1)

is the Lotka-Volterra model describing the population dynamics of two competing species (prey-predation population model).

The conditional representation of (8.1) is

$\displaystyle \left\{\vphantom{
\begin{array}{l}
\vspace{2mm} \displaystyle
\do...
...mits_{-\tau}^{0} F_2(s)   y_1 (s)   ds
\biggr]   x_2   ,\end{array}}\right.$$\displaystyle \begin{array}{l}
\vspace{2mm} \displaystyle
\dot x_1   =   \big...
...
\int\limits_{-\tau}^{0} F_2(s)   y_1 (s)   ds
\biggr]   x_2   ,\end{array}$ (8.2)

so to simulate system (8.2) it is necessary to set the following parameters:

- constants $ \varepsilon$, $ \gamma_{1}^{}$ and $ \gamma_{2}^{}$,

- functions F1( . ), F2( . ),

- an initial point x0,
- an initial prehistory y0( . ) = {y0(s), - $ \tau$ $ \leq$ s < 0}.

One can simulate system (8.2) using the function lv45.