Authors:
Ahmed. O. M. Abubaker,DOI NO:
https://doi.org/10.26782/jmcms.2025.12.00008Keywords:
Runge-Kutta method,fourth-order,systems of first-order differential equations,positive solutions,Abstract
The Runge-Kutta method, and especially its fourth-order variant (RK4), is perhaps the most widely adopted method for solving ordinary differential equations (ODEs) and their systems. This paper deals specifically with the RK4 method to explain a system of first-order differential equations, and the ability of the method to converge and stabilize positive solutions. It is well known that standard RK4 is both accurate and stable, but to particularly maintain positivity of solutions, where the model represents physical quantities that must be non-negative, such as populations or concentrations, often requires extra techniques. This paper discusses theoretically the RK4 method and systems, their execution, the need for retention of positivity, and methodologies for retention of positivity. Several illustrative examples are included to demonstrate the application of the method and the difficulty of maintaining positivity as well.Refference:
I. Amirul. Md. Islam et al. “Accurate Solutions of Initial Value Problems for Ordinary Differential Equations with the Fourth Order Runge Kutta Method.” Journal of Mathematics Research, 7 (2015): 41. 10.5539/jmr.v7n3p41.
II. Bazuaye, F. E. “A new 4th order hybrid Runge-Kutta methods for solving initial value problems (IVPs).” Pure and Applied Mathematics Journal 7.6 (2018): 78-87.
https://www.sciencepublishinggroup.com/article/10.11648/j.pamj.20180706.11
III. Blanes. S. et al. “Positivity-preserving methods for ordinary differential equations.” ESAIM: Mathematical Modelling and Numerical Analysis (2021). 10.1051/m2an/2022042.
IV. Botelho. F. et al. “On the Numerical Solution of First Order Ordinary Differential Equation Systems.” (2020): 498-511. 10.1201/9780429343315-29
V. Candan. T. et al. “Existence Results for Positive Periodic Solutions to First-Order Neutral Differential Equations.” Mediterranean Journal of Mathematics (2024) 10.1007/s00009-024-02635-y
VI. Dhage. B. et al. “Approximating positive solutions of PBVPs of nonlinear first order ordinary quadratic differential equations.” Appl. Math. Lett., 46 (2015): 133-142. 10.1016/j.aml.2015.02.023.
VII. Haiyan Wang et al. “Positive periodic solutions of singular systems of first order ordinary differential equations.” Appl. Math. Comput., 218 (2010): 1605-1610. 10.1016/j.amc.2011.06.038.
VIII. Ibrahim, Salisu. “Solution of First-Order Differential Equation Using Fourth-Order Runge-Kutta Approach and Adams Bashforth Methods.” International Journal on Recent and Innovation Trends in Computing and Communication 11.11 (2023).https://ijritcc.org/index.php/ijritcc/article/view…
IX. Jemal Demsie Abraha et al. “Comparison of Numerical Methods for System of First Order Ordinary Differential Equations.” Pure and Applied Mathematics Journal, 9 (2020): 32. 10.11648/j.pamj.20200902.11.
X. Jingwei Hu et al. “A Second-Order Asymptotic-Preserving and Positivity-Preserving Exponential Runge-Kutta Method for a Class of Stiff Kinetic Equations.” Multiscale Model. Simul., 17 (2018): 1123-1146. 10.1137/18m1226774.
XI. Martin Redmann et al. “Runge-Kutta methods for rough differential equations.” ArXiv, abs/2003.12626 (2020). 10.31390/josa.3.4.06.
XII. Shior. M., et al. “Solution of First Order Ordinary Differential Equations Using Fourth Order Runge-Kutta Method with MATLAB.” International Journal of Mathematics and Statistics Studies 12.1 (2024): 54-63. 10.37745/ijmss.13
XIII. Stephan Nüßlein et al. “Positivity-Preserving Adaptive Runge-Kutta Methods.” ArXiv, abs/2005.06268 (2020):155-179. 10.2140/camcos.2021.16.155.
XIV. Toparkus. H. et al. “First-order systems of linear partial differential equations: normal forms, canonical systems, transform methods.” Annales Universitatis Paedagogicae Cracoviensis. Studia Mathematica, 13 (2014): 109 – 132. 10.2478/aupcsm-2014-0009.
XV. Younis A. Sabawi et al. “A compact Fourth-Order Implicit-Explicit Runge-Kutta Type Method for Solving Diffusive Lotka–Volterra System.” Journal of Physics: Conference Series, 1999 (2021). 10.1088/1742-6596/1999/1/012103.
XVI. Zaileha Md Ali et al. “Lotka-Volterra Model of Wastewater Treatment in Bioreactor System using 4th Order Runge-Kutta Method.” Science Letters (2022). 10.24191/sl.v16i1.15284.

