[R] Euler & Runge-Kutta

[Thomas Petzoldt]

Am 07.11.2016 um 21:52 schrieb Franklin Bretschneider:
> Hello Tom Mosca,
>
> Re:
>
>> Can someone help me with R code to perform approximations to second order differential equations and systems of first order differential equations using Euler's method and Runge-Kutta?  I am not a student and this is not for a test or graded assignment.
>>
>> Examples (unrelated to each other):
>>
>> h = 0.1
>>
>> 1.  3(t^2)y'' - 5ty' + 5y = 0
>>     y(1) = 0, y'(1) = 2/3
>>
>> 2.  Lotka-Volterra
>>     x' = x(3-y)
>>     y' = y(x-3)
>>
>
>
> For solving differential equations, the famous "lsoda" solver is best, far better than the simple Euler method, and also better than Runge & Kutta.
> Angels, or very nice people, implemented solving methods using the lsoda into R. Download the package "deSolve" and the world of numerical solutions is at your feet.

deSolve contains all of this: Euler, Runge-Kutta, lsoda and more ... and 
you will find many examples, papers, tutorials and books, and a special 
mailing list (special interest group) at:

http://desolve.r-forge.r-project.org

Have fun!

Thomas Petzoldt

>
> Succes, Franklin
> -----

Thanks, Franklin :)

>
>
>
>
> Franklin Bretschneider
> Dept of Biology
> Utrecht University
> bretschr at xs4all.nl
>
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