Ask HN: Using REST design for complex function calls?

I like everything I've read about REST but am confused about how to use REST designs for an API with mostly complex, math-y function calls that compute values & return them.

Because the functions require complex - potentially, arbitrarily large - inputs, it's too difficult to pass them in via GETs.

Is there discussion or articles somewhere about using REST for computational APIs rather than for resource-based APIs?