lttb-bench

Started as speed comparison of different lttb implementations for Python.

Morphed into attempt at cython implementation which seemed to work and was faster than the two python versions, but still way slower than the plain C.

ARGH.

Finally, I found three different mistakes I made in the translation from C which when fixed, resulted in the cython implementation performing within 10 to 15% of the C one.

See the notebook for more detail, and how to run this.

Random notes

To get cython 3 installed, I had to:

poetry add --allow-prereleases cython@latest

Pythran module compilation

The Pythran module lttb_pt is compiled with:

poetry run pythran lttb_pt.py