DCL:MATH2:ODELIB: Ordinary Differential Equation (Runge-Kutta): Explanation of Subroutines
Performs integration with the selected stepper routine to satisfy the required precision.
CALL ODRKDV(N,STEPER,FCN,T,TINT,DT,X,WORK)
N (I) Number of variables of integration (integrands). (i) STEPER Name of procedure Name of selected stepper routine. FCN Name of procedure Name of subroutine that calculates DX. (i) T (R) Value of the independent variable t at which to begin integration. The final step t (TEND) is outputted at RETURN. (i/o) TEND (R) Value of independent variable t at which to end integration. (i) DT (I) Initial step width. (i/o) X R(N) Outputs the value of the variable of integration at t=TEND for the inputted value of variable at t=T. (i/o) WORK R(N,M) Working variable. M=7 (for ODRK4) and M=5 (for other subroutines).
SUBROUTINE FCN(N,T,X,DX).