Chris thanks for update. I guess I will go toward the Modelling Toolkit then. I have now transferred all my VBA source code into Julia (basic syntax transposed), but how to link it and present it to the solver will take some time.
The RHS of my system of equations (130) have a lot of interlinked terms and also external parameters fixed at run time, although in due course I want to investigate the impact of some of these parameters(or coefficients) in front of the dependant variables through an optimization engine, which I am yet to define. Do you have a recommendation for a Julia optimization engine that could ultimately call my Julia simulation program and optimize a user defined Objective Function, subject to a list of constraints (equalities and inequalities)? I would like to develop my ODE solver approach so that it won’t limit my ability to do the optimization work, which is the final objective of the project.
Any thoughts appreciated
Thanks,
Peter