4th order runge-kutta method

[FNL]

please i'll like to ask if someone have a code written in c++ or in foltran90 on 4th order runge-kutta method of numerical computation.
thanks

[robphy]

http://www.google.com/search?q=+rk4

[FNL]

http://www.google.com/search?q=+rk4

Thank you