JAX and Numpy functions: How to structure them?

[jakharkaran]

This repository contains a 2D Navier-Stokes equation solver and data processing methods. The solver, written using the JAX library, is computationally expensive and leverages GPU acceleration. The less intensive post-processing methods use NumPy.

Some functions are required by both the solver and post-processing. Currently, duplicate copies exist – one for JAX and one for NumPy. What is the best way to optimize this code structure?

• Passing a backend variable backend = 'numpy' or 'jax': Suitable for functions where the underlying structure is identical between NumPy and JAX, with only the library calls differing
• Write all the functions in JAX (Need to think over it) Pros:
  • User friendliness Cons:
  • Requires careful consideration of JAX-specific function implementations.

[rmojgani]

Also at low resolutions, numpy is faster than gpu-jax, so ability to run on either is beneficential, falling back to numpy when jax is not installed is also favorable

[jakharkaran]

For the solver, At low resolution, JAX-CPU is faster than JAX-GPU. I haven't tested for numpy. I can mention this in the readme for now.

[rmojgani]

I mean for this reason, it is good to have it as a selectionable option, even for the runs

[jwallwork23]

A colleague just told me about the Python "Array API" concept, which might be useful reading for this: https://data-apis.org/array-api/latest/purpose_and_scope.html#stakeholders