Tag Archives: John .C. Butcher

The RK-Nystrøm Method

In “A History Of Runge Kutta Methods” (Applied Numerical Mathematics, 20, 1996, pp 247-260), J.C. Butcher presents a set of coefficients for a 5th order RK method as derived by Kutta. The tableau is shown below:

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However, Butcher indicates that Kutta’s 5th order coefficients had slight errors, which were subsequently corrected by Nystrøm in 1925. The method with these coefficients are more commonly known as the RungeKutta – Nystrøm method. The tableau for the Nystrom coefficients are :

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 The Generalized RK formulation can then be used to solve a set of ODE’s.

Generalized Runge Kutta Formulation

For RK methods of order 4 and higher, the inter-stage vectors (k’s) can be represented using the following formulation (Atkinson et al, Numerical Solution of ODE’s):

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The solution at t(n+1) is given by

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J.C. Butcher (Numerical Methods for ODE’s, 2nd Edition) invented the “Butcher tableau” methodology of representing the coefficients a(i,j), b(j) and c(j) for the Runge Kutta methods. The general format of such a tableau is

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 The Butcher tableau for the most popular RK4 method thus becomes:

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The use of the Butcher tableau, along with the generalized formulation from Atkinson, provides an easy methodology for numerical integration of ODEs.