PyPy is great for loopy/branchy code with lots of function calls. Things that you haven’t done the mental gymnastics to vectorize. That being said, in my line of work, when Python is the bottleneck, a little bit of numpy goes a long way, especially if you orient your axes around the reductions you have planned.
The other thing I’ll say for pypy is that by demonstrating that a Python interpreter written in Python can be faster than Python, it’s pushed CPython to improve performance as well. Not that CPython developers wouldn’t pursue performance gains on their own, but pypy offers a specific target, and we’ve all benefited from the comparison.
The other thing I’ll say for pypy is that by demonstrating that a Python interpreter written in Python can be faster than Python, it’s pushed CPython to improve performance as well. Not that CPython developers wouldn’t pursue performance gains on their own, but pypy offers a specific target, and we’ve all benefited from the comparison.