# Polars 1.3.0 — Python Polars 1.3.0

- Product: Polars (https://whatsnew.fyi/product/polars)
- Vendor: Polars
- Date: 2024-07-28
- Version: 1.3.0
- Original notes: https://github.com/pola-rs/polars/releases/tag/py-1.3.0
- Permalink: https://whatsnew.fyi/product/polars/releases/1.3.0

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

---

- **added** — Expose binary_elementwise_into_string_amortized for plugin authors
- **added** — Expose allocator to capsule
- **added** — Support authentication with HuggingFace login
- **added** — Support "BY NAME" qualifier for SQL "INTERSECT" and "EXCEPT" set ops
- **added** — Support PyCapsule Interface in DataFrame & Series constructors
- **added** — Implement Arrow PyCapsule Interface for Series/DataFrame export
- **added** — Implement forward/backward fill for all types
- **added** — Implement is_in operation on decimal type
- **added** — Support hf:// in read_(csv|ipc|ndjson) functions
- **added** — Allow literals in sort
- **added** — Cloud support for NDJSON
- **added** — Support API token for scanning hf://
- **changed** — Decompress in CSV / NDJSON scan
- **changed** — Ensure unique names in HConcat
- **changed** — Write data at table level in write_excel
- **changed** — Optimise read_excel when using "calamine" engine with the latest fastexcel
- **changed** — Expose 'strict' argument to 'is_in'
- **changed** — Release the GIL in collect_schema
- **fixed** — Properly write nest-nulled values in Parquet
- **fixed** — Improve default write_excel int/float format when using a dark "table_style"
- **fixed** — Fix from_arrow for struct type
- **fixed** — Fix bool/string usage of "column_totals" parameter in write_excel

##### 🚀 Performance improvements

- Ensure metadata flags are maintained on vertical parallelization (#17804)
- Ensure only nodes that are not changed are cached in collapse optimizer (#17791)
- Use bitflags for OptState (#17788)
- Remove async directory auto-detection (#17779)
- Fix accidental quadratic horizontal concat (#17783)
- Batch parquet integer decoding (#17734)
- Use mmap-ed memory if possible in Parquet reader (#17725)
- Use bitflags for function options (#17723)
- Also set target features and tune cpu for CC (#17716)
- Introduce `MemReader` to file buffer in Parquet reader (#17712)

##### ✨ Enhancements

- Expose binary\_elementwise\_into\_string\_amortized for plugin authors, recommend `apply_into_string_amortized` instead of `apply_to_buffer` (#17903)
- Expose allocator to capsule (#17817)
- Decompress in CSV / NDJSON scan (#17841)
- Ensure unique names in HConcat (#17884)
- Support authentication with HuggingFace login (#17881)
- Enable collection with gpu engine (#17550)
- Support "BY NAME" qualifier for `SQL` "INTERSECT" and "EXCEPT" set ops (#17835)
- Write data at table level in `write_excel` (#17757)
- Support PyCapsule Interface in DataFrame \& Series constructors (#17693)
- Implement Arrow PyCapsule Interface for Series/DataFrame export (#17676)
- Raise informative error instead of panicking when passing invalid directives to `to_string` for Date dtype (#17670)
- Implement forward/backward fill for all types (#17861)
- Implement `is_in` operation on decimal type (#17832)
- Optimise `read_excel` when using "calamine" engine with the latest `fastexcel` (#17735)
- Support `hf://` in  `read_(csv|ipc|ndjson)` functions (#17785)
- Allow literals in sort (#17780)
- Expose 'strict' argument to 'is\_in' (#17776)
- Release the GIL in `collect_schema` (#17761)
- Cloud support for NDJSON (#17717)
- Support API token for scanning `hf://` (#17682)

##### 🐞 Bug fixes

- Scanning '%' from cloud (#17890)
- Raise suitable error when invalid column passed to `get_column_index` (#17868)
- Respect `glob=False` for cloud reads (#17860)
- Properly write nest-nulled values in Parquet (#17845)
- Improve default `write_excel` int/float format when using a dark "table\_style" (#17869)
- Fix `from_arrow` for struct type (#17839)
- Fix bool/string usage of "column\_totals" parameter in `write_excel` (#17846)
- Infer decimal scales on mixed scale input (#17840)
- Don't ignore timezones in list of dicts constructor (#14211)
- Raise on unsupported fill strategy dtype (#17837)
- Properly write nested `NullArray` in Parquet (#17807)
- Check input type on list.to\_struct (#17834)
- Fix right join schema (#17833)
- Simultaneous usage of `named_expr` and `schema` in `pl.struct` (#17768)
- Fix projection pusdhown of literals without names (#17778)
- Don't expand HTTP paths (#17774)
- Check funtion input len at expansion (#17763)
- Don't panic in invalid agg\_groups (#17762)
- Raise empty struct (#17736)
- Fix GC logic in `write_ipc` (#17752)
- Panic in pl.concat\_list and list.concat on empty inputs (#17742)
- Fix out nullability for structs coming from arrow (#17738)
- Percent encode for Hugging Face paths (#17718)

##### 📖 Documentation

- Updating the join example input for rust for consistency with python example (#17898)
- Improve filter documentation (#17755)
- Reword "how" param docstring entry for 'semi' and 'anti' `join` types for clarity (#17843)
- Mention `read_*` functions in Hugging Face section in user guide (#17799)
- Show return type for Series attributes in API reference (#17759)
- Add function with multiple arguments example to `Expr.map_batches` (#17789)
- Add Hugging Face section to user guide (#17721)

##### 📦 Build system

- Update Rust toolchain to `nightly-2024-07-26` (#17891)
- Correctly reference released package in optional dependencies (#17691)

##### 🛠️ Other improvements

- On Python release, trigger docs build after API reference build (#17904)
- Set `uv pip install` to verbose (#17901)
- Fix broken `typos

_[Truncated at 4000 characters — full notes: https://github.com/pola-rs/polars/releases/tag/py-1.3.0]_