(48G 49G 50G) Runge-Kutta Diff Eqn solver

[rcthacker]

Thank you again, Werner. More thoughts on your responses:

"Having never used the differential equation solver in the 49/50, I had to look up how to use it.
Given Y' = F(X,Y), with X the independent and Y the dependent variable, it expects an equation or a program to return the value of Y',

"Instead of an equation for F, the calculator also accepts a program,

"It helps if you know that equations are really stored as programs.

Equations are stored as programs?

How or where did you learn that a procedure could be substituted for the RHS of the DE? Was this characteristic also in the 48G and 49G firmware? Interesting that the issue was never raised back then. Or, I suppose it would have been addressed in succeeding User Guides/References The work-around or its need does not seem consistent with a straight-forward Runge-Kutta formulation. Somewhat troubling.