How to Input Equations from External Files

[mheibels]

I haven't used FORTRAN in a very long time (Punch Cards) and I am trying to create a utility that finds the zeros of non-linear functions. I would like to generalize the method to the point that I don't have to recompile for each different equation. I want to pass the equation through my input file via some sort of read statement, but I'm unable to remember how this is done. Is anyone aware of a simple wat to do this ?

Thanks in advance for any assistance.

[Jugoslav_Dujic]

There's no "a simple way" -- since Fortran is compiled language, any expression entered at run-time must be re-parsed, i.e. interpreted.

There's free function parser by Stuart Midgley you can use. Note that the method, in principle, comes down to interpreting, thus it's necessarily slower than using pre-compiled code. Also, I've built a graphing tool around that parser which you can take a look at here.

Jugoslav