[FEA] Remove special-case implementation of `MultiIndex.isin`
Open
feature request
Performance
Python
- Dominant language
- C++
- Stars
- 9.8k
- Forks
- 1.1k
- Avg merge
- 3d 6m
- Merged PRs (30d)
- 278
Description
**Is your feature request related to a problem? Please describe.**
`isin` is implemented "by-hand" for `MultiIndex` by going via the frame representation and then calling `merge`. This means that any updates to correctness/performance of `DataFrame.isin` must be hand-ported to the `MultiIndex` case.
**Describe the solution you'd like**
`MultiIndex.isin` should do necessary pre-/post-processing and call `DataFrame.isin` rather than re-implementing the core algorithm.
**Describe alternatives you've considered**
n/a
Contributor guide
Assessment
This issue has not been assessed yet.