# Polars 1.6.0 — Python Polars 1.6.0

- Product: Polars (https://whatsnew.fyi/product/polars)
- Vendor: Polars
- Date: 2024-08-28
- Version: 1.6.0
- Original notes: https://github.com/pola-rs/polars/releases/tag/py-1.6.0
- Permalink: https://whatsnew.fyi/product/polars/releases/1.6.0

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'.

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- **changed** — Use Altair in DataFrame.plot
- **changed** — Allow mapping as syntactic sugar in str.replace_many
- **changed** — Respect input time zone if input is pandas Timestamp
- **changed** — Improve Schema and DataType interop with Python types
- **added** — Add POLARS_BACKTRACE_IN_ERR for debugging
- **added** — IR serde
- **changed** — Support pre-signed URLs for cloud scan
- **changed** — Support the most recent version of duckdb_engine connections via read_database
- **added** — Support empty structs
- **changed** — Allow float in interpolate_by by column
- **changed** — Make show_versions more responsive
- **fixed** — Enable CSE in eager if struct are expanded
- **fixed** — Treat explode as gather
- **fixed** — Parquet nested values that span several pages
- **fixed** — Support reading empty parquet files
- **fixed** — Recurse on map field during type conversion
- **fixed** — Allow search_sorted on boolean series
- **fixed** — Mark Expr.lower_bound and Expr.upper_bound as returning scalar
- **fixed** — Fix compressed ndjson row count

##### 💥 Unstable Breaking changes
*These API's were marked unstable* and are allowed to change.

- Use Altair in DataFrame.plot (#17995)

##### 🚀 Performance improvements

- Parquet do not copy uncompressed pages (#18441)
- Several large parquet optimizations (#18437)
- Batch Plain Parquet UTF-8 verification (#18397)
- Partition metadata for parquet statistic loading (#18343)
- Fix accidental quadratic parquet metadata (#18327)
- Lazy decompress Parquet pages (#18326)
- Don't rechunk aligned chunks in owned\_binary\_chunk\_align (#18314)
- Batch `DELTA_LENGTH_BYTE_ARRAY` decoding (#18299)
- Slice pushdown for SimpleProjection (#18296)
- Use direct path for `time`/`timedelta` literals (#18223)
- Speedup ndjson reader `~40%` (#18197)
- Skip parquet page when unneeded (#18192)

##### ✨ Enhancements

- Use Altair in DataFrame.plot (#17995)
- Allow mapping as syntactic sugar in `str.replace_many` (#18214)
- Respect input time zone if input is pandas Timestamp (#18346)
- Improve Schema and DataType interop with Python types (#18308)
- Add POLARS\_BACKTRACE\_IN\_ERR for debugging (#18333)
- IR serde (#18298)
- Improve decimal\_comma error message (#18269)
- Support pre-signed URLs for cloud scan (#18274)
- Support the most recent version of "duckdb\_engine" connections via `read_database` (#18277)
- Support empty structs (#18249)
- Allow float in interpolate\_by by column (#18015)
- Make show\_versions more responsive (#18208)

##### 🐞 Bug fixes

- Enable CSE in eager if struct are expanded (#18426)
- Treat `explode` as `gather` (#18431)
- Parquet nested values that span several pages (#18407)
- Support reading empty parquet files (#18392)
- Recurse on map field during type conversion (#15075)
- Allow search\_sorted on boolean series (#18387)
- Mark Expr.(lower|upper)\_bound as returning scalar (#18383)
- Fix compressed ndjson row count (#18371)
- Use correct column names when there are no value columns in unpivot (#18340)
- Parquet several smaller issues (#18325)
- Fix group-by slice on all keys (#18324)
- Compute joint null mask before calling rolling corr/cov stats (#18246)
- Several `scan_parquet(parallel='prefiltered')` problems (#18278)
- Json feature flag missing imports (#18305)
- Check groups in group-by filter (#18300)
- Parquet delta encoding for 0-bitwidth miniblocks (#18289)
- Arguments for `upsample` only have to be sorted within groups (#18264)
- Use appropriate bins in `hist` when `bin_count` specified (#16942)
- Raise suitable error on unsupported `SQL` set op syntax (#18205)
- Fix invalid state due to cached IR (#18262)
- Fix failed AWS credential load from '~/.aws/credentials' due to formatting (#18259)
- Fix panic streaming parquet scan from cloud with slice (#18202)
- Consistently round half-way points down in dt.round (#18245)
- Fix duplicate column output and panic for `include_file_paths` (#18255)
- Fix unit null rank (#18252)
- Use physical for row-encoding (#18251)
- Convert date and datetime in literal construction (#16018)
- Fix gather str as lit (#18207)

##### 📖 Documentation

- Add date\_range and datetime\_ranges examples without `eager=True` (#18379)
- Fix incorrect comments in `group_by_dynamic` (#18415)
- Alphabetise methods in Python API reference (#18380)
- Document POLARS\_BACKTRACE\_IN\_ERR env var (#18354)
- Add missing aggregation entries (#18334) (#18341)
- Add missing `Series` methods to API reference (#18312)
- Document `DataFrame.__getitem__` and `Series.__getitem__` (#18309)
- Fix typos and add see also links to struct name expressions (#18282)
- Improve decimal\_comma error message (#18269)
- Clarify `coalesce` behaviour in `join_asof` (#18273)
- Add note to `Expr.shuffle` differentiating from df method (#18266)
- Improve formatting and consistency of various docstrings (#18237)
- Add missing "Parameters" section to `bin.size` expr docstring (#18222)
- Fix column name output in example of `DataFrame.map_

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