How does DataFrame.interpolation() work (in its source code)?

[benjamin_z]

I could not find the declarations of the single methods of DataFrame.interpolation()'s "method"-parameter, therefore:

How does pandas' DataFrame.interpolation() work in relation to the amount of rows it considers,

• a) is it just the row before the NaNs and the row right after?
• b) Or is it the whole DataFrame (how does that work at 1 million rows?)
• c) other way (please explain).

feel free to share the link to the source-code, since https://github.com/pandas-dev/panda...9abf539867a8cd481/pandas/core/frame.py#L10916 didnt include the "method"'s declarations (for example "polynomial").