**rk34**,
a Python code which
implements Runge-Kutta ODE solvers of orders 3 and 4.

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

**rk34** is available in
a MATLAB version and
an Octave version and
a Python version.

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- predator_rk3_phase.png a phase plot produced by predator_rk3().
- predator_rk4_phase.png a phase plot produced by predator_rk4().
- predator_rk3_plot.png a solution plot produced by predator_rk3().
- predator_rk4_plot.png a solution plot produced by predator_rk4().