Split the main program up into sensible subroutines

edoddridge / aronnax

An idealised isopycnal model that can be run either with n+1/2 layers, or with n layers and variable bathymetry.

http://aronnax.readthedocs.io/en/latest/

MIT License

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Split the main program up into sensible subroutines #70

Closed axch closed 7 years ago

axch commented 7 years ago

Benefits:

Increase comprehensibility by naming semantic parts, and by spelling out the means of communication between them (especially in light of the intent declarations called for by Issue #54).
Reduce duplication of code by naming and reusing repeated chunks (like the state derivative computation), and gain comprehensibility and hackability thereby.
Increase precision of procedure-wise profiling, per the complaint in Issue #48.
Increase the number of easy attachment points for a hypothetical Python driver, per f2py.

axch commented 7 years ago

I've started working on this, and it causes a lot of code rearrangement, so we probably shouldn't do anything more to the core until this completes, on pain of merge conflicts.

axch commented 7 years ago

An unexpected beneficial consequence of this project: the time needed to compile the core has fallen drastically. I'm guessing there's some kind of flow or alias analysis in the compiler whose runtime scales with the product of #variables by #statements in some function, or #variables squared, or some such.

Or, perhaps, variables declared intent(in) are faster to compile than mutable ones.

edoddridge commented 7 years ago

That's a nice side effect!