Suggestion: Use subsampling and early stopping to speed up medoid calculation.

[bendavidsteel]

Hi! Love the library, great work!

Using medoids for large tasks takes ages, I left a run going overnight and it didn't finish. So to speed it up, I adding subsampling and early stopping to the medoid function, and anecdotally it massively sped up the calculation and produced results that look good.

I haven't done any more thorough testing which is why I haven't submitted a PR, but does this sounds like something that would be merged into the project?

[lmcinnes]

That sounds like a great idea. I hadn't really stress tested it for really large workloads, so it is definitely possible it doesn't scale as well as it should. What you are proposing seems both simple and effective, which sounds great to me. A PR would be most welcome!