Philipp Hoffmann

I looked into this for a bit and the internal logic behind `df_new = pd.read_csv("out_mh.csv", header=[0,1], index_col=[0])` that infers a third header row has at least four more minor issues...

Happens on main as well, including the non deterministic success in a minority of attempts.

> There are probably some tricks we can try like using a static lookup table instead of branches: I tried that, but it did not improve the situation on my...

I now have a version of the date time conversion that is correct and tested and runs up to 2.5x faster than main and the previous version before the regression...

> Possibly related?: https://github.com/pandas-dev/pandas/issues/57035 Good find, but the regression here should be unrelated to that plotting issue. Converting 1M timestamps takes some milliseconds, but the referenced regression is in the...