FORTRAN 90 - DVERK? - initial condition solver

AI Thread Summary
FORTRAN users seeking a routine similar to MATLAB's ODE45 for solving initial condition problems in ODEs are advised to consider coding their own solutions. Simple methods like Euler's method and 4th order Runge-Kutta are recommended for their ease of implementation and accuracy. However, both DVERK and ODE45 utilize adaptive step-size techniques, making them more complex to replicate. A reference to RKSUITE is provided as a potential resource for further exploration. Custom coding may be necessary for those requiring specific functionalities in FORTRAN 90.
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Hi,

I am new to FORTRAN and am trying to work with a system of ODE's. Does someone know of a routine like DVERK for solving initial condition problems for FORTRAN 90?

In MATLAB I would simply use ODE45. I just need something similar.

Thank you!
 
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Your best bet would be to code your own. Start with a Eulers method, this is very simple though not so precise. A 4th order Runga Kutta routine is also easy to code and is quite accurate. Do a bit of web searching and have a go at it.
 
Yeah both the Euler and the fixed step size Runge-Kutta are simple implementations. The DVERK and ode45 both use adaptive step-size routines, and it gets much more complicated there.
 
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